ORCID Profile
0000-0001-9142-2126
Current Organisations
UNSW Sydney
,
City University of Hong Kong
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Publisher: American Chemical Society (ACS)
Date: 29-03-2016
DOI: 10.1021/ACS.JPCLETT.6B00428
Abstract: The {010} and {110} crystal facets of monoclinic bismuth vanadate (m-BiVO4) has been demonstrated to be the active reduction and oxidation sites, respectively. Here, we show using dual-faceted m-BiVO4 with distinctly different dominant exposed facets, one which is {010}-dominant and the other {110}-dominant, contrary to prediction, the former m-BiVO4 exhibits superior photooxidation activities. The population of photogenerated electrons and holes on the surface are revealed to be proportional to the respective surface areas of {010} and {110} exposed on m-BiVO4, as evidenced by steady-state photoluminescence (PL) measurements in the presence of charge scavengers. The better photoactivity of {010}-dominant m-BiVO4 is attributed to prompt electron transfer facilitated by the presence of more photogenerated electrons on the larger {010} surface. Additionally, the greater extent of electron trapping in {110}-dominant m-BiVO4 also deteriorates its photoactivity by inducing electron-hole pair recombination.
Publisher: American Chemical Society (ACS)
Date: 08-06-2020
Publisher: Beilstein Institut
Date: 24-06-2014
DOI: 10.3762/BJNANO.5.102
Abstract: Photovoltaic characteristics of dye-sensitized solar cells (DSSCs) using TiO 2 nanotube (TNT) arrays as photoanodes were investigated. The TNT arrays were 3.3, 11.5, and 20.6 μm long with the pore diameters of 50, 78.6, and 98.7 nm, respectively. The longest TNT array of 20.6 μm in length showed enhanced photovoltaic performances of 3.87% with significantly increased photocurrent density of 8.26 mA·cm −2 . This improvement is attributed to the increased amount of the adsorbed dyes and the improved electron transport property with an increase in TNT length. The initial charge generation rate was improved from 4 × 10 21 s −1 ·cm −3 to 7 × 10 21 s −1 ·cm −3 in DSSCs based on optical modelling analysis. The modelling analysis of optical processes inside TNT-based DSSCs using generalized transfer matrix method (GTMM) revealed that the amount of dye and TNT lengths were critical factors influencing the performance of DSSCs, which is consistent with the experimental results.
Publisher: American Chemical Society (ACS)
Date: 11-10-2016
Abstract: Water oxidation on visible-light-active bismuth vanadate (BiVO
Publisher: Elsevier BV
Date: 07-2016
Publisher: Elsevier BV
Date: 08-2017
Publisher: Elsevier BV
Date: 12-2018
Publisher: Wiley
Date: 03-07-2017
Publisher: American Chemical Society (ACS)
Date: 13-11-2015
Publisher: American Chemical Society (ACS)
Date: 24-03-2011
DOI: 10.1021/JP1090137
Publisher: American Chemical Society (ACS)
Date: 31-07-2007
DOI: 10.1021/CM0702969
Publisher: Wiley
Date: 12-07-2016
Abstract: A stable and selective electrocatalyst for CO2 reduction was fabricated by covalently attaching graphitic carbon nitride onto multiwall carbon nanotubes (g-C3 N4 /MWCNTs). The as-prepared composite is able to reduce CO2 exclusively to CO with a maximum Faraday efficiency of 60 %, and no decay in the catalytic activity was observed even after 50 h of reaction. The enhanced catalytic activity towards CO2 reduction is attributed to the formation of active carbon-nitrogen bonds, high specific surface area, and improved material conductivity of the g-C3 N4 /MWCNT composite.
Publisher: Elsevier BV
Date: 11-2020
Publisher: Elsevier BV
Date: 06-2015
Publisher: American Chemical Society (ACS)
Date: 29-07-2021
Publisher: American Chemical Society (ACS)
Date: 26-05-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2008
DOI: 10.1039/B803912G
Abstract: Platinum nanoparticles embedded in a hollow porous carbon shell prepared by a photocatalytic reaction acted as a reusable catalyst for the aerobic oxidation of alcohols under atmospheric pressure of oxygen in water.
Publisher: Wiley
Date: 11-09-2018
Abstract: Cuprous Oxide (Cu
Publisher: American Chemical Society (ACS)
Date: 11-07-2022
Publisher: Elsevier BV
Date: 03-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0QM01103G
Abstract: MOFs/grephene aerogel capture particulate matter and in situ heat treat for high-performance energy applications.
Publisher: American Chemical Society (ACS)
Date: 22-04-2011
DOI: 10.1021/AM200147B
Abstract: This work reports the use of sodium fluoride (in ethylene glycol electrolyte) as the replacement of hydrofluoric acid and ammonium fluoride to fabricate long and perpendicularly well-aligned TiO₂ nanotube (TNT) (up to 21 μm) using anodization. Anodizing duration, applied voltage and electrolyte composition influenced the geometry and surface morphologies of TNT. The growth mechanism of TNT is interpreted by analyzing the current transient profile and the total charge density generated during anodization. The system with low water content (2 wt %) yielded a membrane-like mesoporous TiO₂ film, whereas high anodizing voltage (70 V) resulted in the unstable film of TNT arrays. An optimized condition using 5 wt % water content and 60 V of anodizing voltage gave a stable array of nanotube with controllable length and pore diameter. Upon photoexcitation, TNTs synthesized under this condition exhibited a slower charge recombination rate as nanotube length increased. When made into cis-diisothiocyanato-bis(2,2̀-bipyridyl-4,4̀-dicarboxylato) ruthenium(II) bis (tetrabutyl-ammonium)(N719) dye-sensitized solar cells, good device efficiency at 3.33 % based on the optimized TNT arrays was achieved with longer electron time compared with most mesoporous TiO₂ films.
Publisher: American Chemical Society (ACS)
Date: 09-03-2011
DOI: 10.1021/JP1113575
Publisher: American Chemical Society (ACS)
Date: 12-07-2018
Publisher: American Chemical Society (ACS)
Date: 07-07-2010
DOI: 10.1021/JZ100728Z
Publisher: Wiley
Date: 12-07-2016
Publisher: Wiley
Date: 24-09-2018
Publisher: Elsevier BV
Date: 12-2019
Publisher: Wiley
Date: 24-08-2018
Abstract: Pulsed electrodeposition has been introduced to deposit ultrathin flakes of Co
Publisher: Wiley
Date: 17-10-2016
Abstract: Au-Ni core-shell nanorods (NRs) and Au-Pt-Ni core-sandwich-shell NRs are synthesized and exhibit high activity for selective H
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5TA04203H
Abstract: Sponge-template TiO 2 -reduced graphene oxide (RGO) is prepared with improved dispersion of TiO 2 on RGO sheets for efficient photoelectro-oxidation of ethanol.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0TA01180K
Abstract: A comprehensive survey on preparation methods of powdered or thin-film Bi-based photocatalysts is provided, comparing he erse approaches and their advantages and limitations in the context of photocatalytic and photoelectrochemical applications.
Publisher: Royal Society of Chemistry (RSC)
Date: 2011
DOI: 10.1039/C1CC13738G
Abstract: The CuInS(2) (CIS) nanoparticles were wrapped uniformly throughout the inner and outer walls of TNTs (TNT) by using square wave pulsed-electrodeposition. This structure enables the CuInS(2)-TiO(2) (CIS-TNT) to exhibit p-n junction diode behavior and enhanced photoelectrochemical properties.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0SE01901A
Abstract: A facile chemical treatment employing a reducing agent sodium sulfite with a mild reduction activity is used to alter the surface states of BiVO 4 photoanodes. The sulfite-treated BiVO 4 (S-BiVO 4 ) exhibits an enhanced photoelectrochemical performance.
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9GC00734B
Abstract: Oxygen functionalities on GIO/GO are involved in the formation of active Al sites potentially with a microwave-absorbing ability, which facilitates glucose–fructose isomerisation in water.
Publisher: Springer Science and Business Media LLC
Date: 09-04-2009
Publisher: American Chemical Society (ACS)
Date: 02-09-2015
Abstract: Carrier density, photocharge transfer kinetics, and charge transfer resistance of the anodized Cu-Cu2O-CuO photocathode were greatly improved using thermal treatment with urea. Time-correlated single-photon counting (TCSPC) results revealed the faster electron transfer kinetics from Cu2O to CuO in the urea-treated Cu-Cu2O-CuO composite photoelectrodes. Preservation of the metallic copper component via the intermediate Cu3N during the treatment facilitated higher bulk conductance of the Cu-Cu2O-CuO photocathode for improved charge transport. Higher carrier density was also observed in the urea-treated photoelectrode, which was possibly attributed to the presence of nitrogen as a dopant. Furthermore, the compact outer layer of CuO protected the underlayer Cu2O from being in direct contact with the aqueous solution. This suppressed the photocorrosion of Cu2O and resulted in the higher photostability of the Cu-Cu2O-CuO film. When these advantages were combined, the urea-treated Cu-Cu2O-CuO film showed a higher photocurrent of 2.2 mA/cm2 and improved stability versus that of the conventional Cu-Cu2O-CuO film (1.2 mA/cm2). To improve the charge transfer kinetics and carrier density, this paper provides a new strategy for synthesizing effective and stable Cu2O-based photoelectrodes by using urea treatment.
Publisher: Wiley
Date: 11-09-2018
Abstract: Towards clean energy: ChemPlusChem presents its special issue on "Future Energy Technology", guest-edited by François Aguey-Zinsou, Zaiping Guo, Yun Hau Ng, and Da-wei Wang. They have complied a multidisciplinary look at the chemistry behind new concepts for clean energy of the future. This issue was born out of the 2018 Future Energy Conference (organized by UNSW, Australia) and features top contributions covering energy storage, materials science and water splitting.
Publisher: Elsevier BV
Date: 12-2018
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5DT00429B
Abstract: Photosensitized ZnO nanorods uniformly coated with CuInS 2 nanoparticles from sequentially pulsed-electrodeposition yielded superior charge transfer ability and great enhancement in photoelectrochemical performance under visible light irradiation.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C6TA10665J
Abstract: A ZnO photocatalyst decorated with platinum nanoparticles and a thin, uniform layer of phenol-derived polymer demonstrated enhanced transportation of photogenerated charge.
Publisher: MDPI AG
Date: 06-12-2016
DOI: 10.3390/EN9121030
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/C9GC02567G
Abstract: Composition-tunable mixed Brønsted/Lewis acids on silica-alumina and silica-alumina-phosphate prepared by the rapid flame spray pyrolysis produce exceptionally high glucose-to-levulinic acid yield, twice that of commercial ZSM-5 and Zeolite X.
Publisher: Wiley
Date: 19-07-2017
Publisher: Elsevier BV
Date: 11-2019
Publisher: Elsevier BV
Date: 06-2014
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C8CS00882E
Abstract: This review summarizes current experimental techniques, including the conventional and the state-of-the-art tools, to examine the key aspects of photocatalysts.
Publisher: Elsevier BV
Date: 07-2020
Publisher: Elsevier BV
Date: 06-2020
Publisher: Wiley
Date: 20-12-2017
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0EE03892J
Abstract: 3.17% efficient Cu 2 ZnSnS 4 –BiVO 4 integrated tandem cell and a large scale 5 × 5 cm integrated CZTS–BiVO 4 tandem device for standalone overall solar water splitting was assembled for the first time.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7RA04185C
Abstract: A multi-step chemical replication method using natural green leaves as templates can produce a porous, visible-light active TiO 2 -based photocatalyst.
Publisher: Wiley
Date: 04-2017
Publisher: Elsevier BV
Date: 09-2019
Publisher: Wiley
Date: 31-12-2016
DOI: 10.1002/AIC.15117
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5TA01237F
Abstract: A photoelectrochemical cell consisting of an enhanced RGO–CuGaS 2 composite photocathode and a CoO x -loaded BiVO 4 photoanode generated photocurrent under simulated sunlight irradiation without any external applied bias.
Publisher: Elsevier BV
Date: 03-2016
DOI: 10.1016/J.JHAZMAT.2015.11.004
Abstract: A newly developed CdS/rGO/CC electrode was prepared based on a flexible carbon cloth (CC) substrate with cadmium sulfide (CdS) nanoparticles and reduced graphene oxide (rGO). The CdS was synthesized using an aerosol-assisted chemical vapor deposition (AACVD) method, and the graphene oxide was thermally reduced on the modified electrode surface. The existence of rGO in the CdS-modified electrode increased the photocurrent intensity of the CdS/rGO/CC-modified electrode by three orders of magnitude, compared to that of the CdS/ITO electrode and two orders of magnitude higher than the CdS/CC electrode. A new visible-light-prompt photoelectrochemical sensor was developed based on the competitive binding reaction of Cu(2+) and CdS on the electrode surface. The results showed that the effect of the Cu(2+) on the photocurrent response was concentration-dependent over the linear ranges of 0.1-1.0 μM and 1.0-40.0 μM with a detection limit of 0.05 μM. The results of a selectivity test showed that this modified electrode has a high response toward Cu(2+) compared to other heavy metal ions. The proposed CdS/rGO/CC electrode provided a significantly high potential current compared to other reported values, and could be a practical tool for the fast, sensitive, and selective determination of Cu(2+).
Publisher: American Chemical Society (ACS)
Date: 04-2011
DOI: 10.1021/JZ2002698
Abstract: We demonstrated for the first time by large-scale ab initio calculations that a graphene/titania interface in the ground electronic state forms a charge-transfer complex due to the large difference of work functions between graphene and titania, leading to substantial hole doping in graphene. Interestingly, electrons in the upper valence band can be directly excited from graphene to the conduction band, that is, the 3d orbitals of titania, under visible light irradiation. This should yield well-separated electron-hole pairs, with potentially high photocatalytic or photovoltaic performance in hybrid graphene and titania nanocomposites. Experimental wavelength-dependent photocurrent generation of the graphene/titania photoanode demonstrated noticeable visible light response and evidently verified our ab initio prediction.
Publisher: Elsevier BV
Date: 11-2020
Publisher: Wiley
Date: 30-05-2019
Publisher: Wiley
Date: 04-05-2020
Publisher: Wiley
Date: 21-07-2016
Abstract: Efficient interfacial charge transfer is essential in graphene-based semiconductors to realize their superior photoactivity. However, little is known about the factors (for ex le, semiconductor morphology) governing the charge interaction. Here, it is demonstrated that the electron transfer efficacy in reduced graphene oxide-bismuth oxide (RGO/BiVO
Publisher: IEEE
Date: 02-2014
Publisher: IEEE
Date: 02-2014
Publisher: American Chemical Society (ACS)
Date: 17-05-2008
DOI: 10.1021/LA800045U
Abstract: Platinum (Pt) nanoparticles encapsulated in microporous carbon with a hollow structure (nPt@hC) were fabricated on the basis of a titanium(IV) oxide (TiO2) photocatalytic reaction. From the tomogram of a s le studied by using a transmission electron microscope (TEM), the Pt nanoparticles were found to be embedded in the carbon shell and were physically separated from each other by the carbon matrix. Owing to this unique structure, the Pt particles showed high resistance to sintering when subjected to thermal treatment at temperatures up to 800 degrees C. As a result, hydrogenation reactions using various heat-treated nPt@hCs as catalysts indicated that loss of catalytic activity was minimized. Thus, the present system will be a promising system for optimizing catalyst nanostructures utilized in processes requiring rigorous conditions.
Publisher: American Chemical Society (ACS)
Date: 06-07-2021
DOI: 10.1021/ACS.CHEMREV.0C01328
Abstract: Global energy and environmental crises are among the most pressing challenges facing humankind. To overcome these challenges, recent years have seen an upsurge of interest in the development and production of renewable chemical fuels as alternatives to the nonrenewable and high-polluting fossil fuels. Photocatalysis, photoelectrocatalysis, and electrocatalysis provide promising avenues for sustainable energy conversion. Single- and dual-component catalytic systems based on nanomaterials have been intensively studied for decades, but their intrinsic weaknesses h er their practical applications. Multicomponent nanomaterial-based systems, consisting of three or more components with at least one component in the nanoscale, have recently emerged. The multiple components are integrated together to create synergistic effects and hence overcome the limitation for outperformance. Such higher-efficiency systems based on nanomaterials will potentially bring an additional benefit in balance-of-system costs if they exclude the use of noble metals, considering the expense and sustainability. It is therefore timely to review the research in this field, providing guidance in the development of noble-metal-free multicomponent nanointegration for sustainable energy conversion. In this work, we first recall the fundamentals of catalysis by nanomaterials, multicomponent nanointegration, and reactor configuration for water splitting, CO
Publisher: Wiley
Date: 10-11-2020
Abstract: Photothermocatalytic ethanol oxidation to acetaldehyde offers an alternative technology in synthesizing high‐value‐added chemicals. However, the practical application is hindered by the competition from overoxidation leading to complete mineralization. Herein, the 1D nanostructured ZnO@zeolitic imidazolate framework‐8 (ZIF‐8) composite is reported as an efficient photothermocatalyst, which shows improved conversion efficiency and high catalytic selectivity and durability compared with the parent ZnO nanorods, for continuous ethanol oxidation in a flow system. The ZnO@ZIF‐8 composite achieves a high selectivity of 91.5% toward acetaldehyde production. The underlying mechanism is probed using electrochemical impedance spectroscopy, N 2 adsorption–desorption isotherms, transient open‐circuit potential, and steady‐state and time‐resolved photoluminescence spectroscopy. Collectively, the probings show that the improved performance originates from 1) facilitated charge separation 2) lowered oxidation potential holes 3) enlarged surface area and 4) preferred reaction routes. This work provides a new perspective for the design of a hybrid photothermocatalyst for selective solar energy conversion into desirable chemicals.
Publisher: Wiley
Date: 23-12-2016
Publisher: Wiley
Date: 11-10-2019
Abstract: A peculiar radical polymerization reaction is presented in which oxygen serves as a cocatalyst, alongside triethylamine, to provide activation with light in the far-red (690 nm, 3 mW cm
Publisher: Royal Society of Chemistry (RSC)
Date: 2013
DOI: 10.1039/C3NR34012K
Abstract: A highly stable p-type cuprous oxide (Cu2O) photoelectrode has been fabricated by direct anodization of the Cu foil, followed by a thermal treatment to introduce a protective layer of copper oxide (CuO) nanowires penetrating the surface of the Cu2O layer. The anodized Cu2O served as the seeding sites for the growth of CuO nanowires. The embedment of CuO nanowires within the Cu2O matrix enhanced the adhesion of the nanowires onto the Cu substrate. In addition, the presence of CuO nanowires on the outer layer of the composite film, in turn stabilized the Cu2O layer by passivating the redox activities of Cu2O when exposed to the environment. This nanostructured p-type Cu2O photoelectrode generated 360 μA cm(-2) of photocathodic current density upon visible light illumination and managed to retain its photocathodic current density after being used and kept for one month. The improvement in photoelectrochemical (PEC) stability by introducing a passive layer of CuO nanowires provides useful insights into the development of a Cu2O photoelectrode, as its stability remained as the main challenge.
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5TA03255E
Abstract: High quality coating of vertically aligned ZnO nanorods with CuInS 2 nanoparticles is achieved by a pulse-regulated electrodeposition method.
Publisher: Wiley
Date: 09-12-2020
Abstract: Photocatalytic and photoelectrochemical processes are two key systems in harvesting sunlight for energy and environmental applications. As both systems are employing photoactive semiconductors as the major active component, strategies have been formulated to improve the properties of the semiconductors for better performances. However, requirements to yield excellent performances are different in these two distinctive systems. Although there are universal strategies applicable to improve the performance of photoactive semiconductors, similarities and differences exist when the semiconductors are to be used differently. Here, considerations on selected typical factors governing the performances in photocatalytic and photoelectrochemical systems, even though the same type of semiconductor is used, are provided. Understanding of the underlying mechanisms in relation to their photoactivities is of fundamental importance for rational design of high-performing photoactive materials, which may serve as a general guideline for the fabrication of good photocatalysts or photoelectrodes toward sustainable solar fuel generation.
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5TA02608C
Abstract: An electrochemical sensing platform based on a hydrothermally synthesized rGO–Co 3 O 4 @Pt nanocomposite was developed for the detection of in situ generated NO.
Publisher: American Chemical Society (ACS)
Date: 17-08-2010
DOI: 10.1021/JZ100978U
Publisher: Wiley
Date: 15-01-2013
Abstract: This work presents insight into the self-photorechargeability of WO(3), whereby the intercalation of positive alkali cations is accompanied by the simultaneous storage of photo-excited electrons. The cyclic voltammetry studies verify the photo-assisted intercalation and de-intercalation of Na(+) and K(+) from the flower structured WO(3). A storage capacity of up to 0.722 C cm(-2) can be achieved in a saturated (0.68 M) K(2)SO(4) electrolyte solution. However, the best photo recharge-discharge stability of the electrode are observed at a lower (0.1 M) cation concentration. At high electrolyte concentrations, the intercalated cations are firmly trapped, as indicated by the structural modifications observed in Raman analysis, resulting in much less photocharging and discharging abilities in subsequent cycles. The study also shows that the stored electrons can be successfully used to generate H(2) with 100 % faradaic efficiency in the absence of light.
Publisher: Wiley
Date: 25-01-2007
Publisher: Elsevier BV
Date: 02-2019
Publisher: Elsevier BV
Date: 08-2006
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C6CP05950C
Abstract: Au–Ag@TiO 2 were prepared using a simple one-step chemical reduction method and used as photoanodes in high-efficiency DSSCs.
Publisher: The Chemical Society of Japan
Date: 05-09-2008
DOI: 10.1246/CL.2008.948
Publisher: American Chemical Society (ACS)
Date: 28-10-2016
Publisher: Wiley
Date: 07-01-2019
Abstract: Conductive metal oxides represent a new category of functional material with vital importance for many modern applications. The present work introduces a new conductive metal oxide V
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5TA05195A
Abstract: ZnO nanorod arrays are used as suitable large area scaffolds to support CdS for improved visible light photoelectrochemical performances.
Publisher: Wiley
Date: 12-07-2017
Abstract: Herein, we demonstrate that the intramolecular electron transfer within a single enzyme molecule is an important alternative pathway that can be harnessed to generate electricity. By decoupling the redox reactions within a single type of enzyme (for ex le, Trametes versicolor laccase), we harvested electricity efficiently from unconventional fuels including recalcitrant pollutants (for ex le, bisphenol A and hydroquinone) in a single-laccase biofuel cell. The intramolecular electron-harnessing concept was further demonstrated with other enzymes, including power generation during CO
Publisher: Elsevier BV
Date: 09-2019
Publisher: Wiley
Date: 23-04-2022
Abstract: The electrocatalytic nitrogen reduction reaction (NRR) provides a sustainable route for NH 3 synthesis. However, the process is plagued by the strong NN triple bond and high reaction barrier. Modification of catalyst surface to increase N 2 adsorption and activation is crucial. Herein, copper nanoparticles are loaded on the oxygen‐deficient TiO 2 , which exhibits an enhanced NRR performance with NH 3 yield of 13.6 µg mg cat −1 h −1 at −0.5 V versus reversible hydrogen electrode (RHE) and Faradaic efficiency of 17.9% at −0.4 V versus RHE compared to the pristine TiO 2 . The enhanced performance is ascribed to the higher electrochemically active surface area, promoted electron transfer, and increased electron density originated from the strong metal‐support interaction (SMSI) between Cu nanoparticles and oxygen‐deficient TiO 2 . The SMSI effect also results in lopsided local charge distribution, which polarizes the adsorbed N 2 molecules for better activation. This work provides a facile strategy toward the electrocatalyst design for efficient NRR under ambient conditions.
Publisher: Elsevier BV
Date: 12-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2012
DOI: 10.1039/C2RA20827J
Publisher: Wiley
Date: 28-08-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1TA05407D
Abstract: This review paper focuses on assessing recent publications that used metal sulfide photoelectrodes for PEC applications, with the aim of evaluating the vital parameters required for the design of metal sulfide photocathodes and photoanodes.
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C4RA13464H
Abstract: Photoactivity and stability of Cu 2 O–CuO heterojunction thin films are enhanced by incorporating an interlayer of TiO 2 . The thin TiO 2 layer minimises the redox reactions at Cu 2 O–electrolyte interface and facilitates charge transfer from Cu 2 O to CuO.
Publisher: Wiley
Date: 03-03-2021
Publisher: American Chemical Society (ACS)
Date: 07-04-2022
Publisher: Elsevier BV
Date: 08-2018
Publisher: Elsevier BV
Date: 03-2021
Publisher: Elsevier BV
Date: 04-2011
Publisher: Elsevier BV
Date: 05-2019
Publisher: MDPI AG
Date: 17-08-2020
DOI: 10.3390/EN13164250
Abstract: Halide perovskite is one of the most promising semiconducting materials in a variety of fields such as solar cells, photodetectors, and light-emitting diodes. Lead halide perovskite single crystals featuring long diffusion length, high carrier mobility, large light absorption coefficient and low defect density, have been attracting increasing attention. Fundamental study of the intrinsic nature keeps revealing the superior optoelectrical properties of perovskite single crystals over their polycrystalline thin film counterparts, but to date, the device performance lags behind. The best power conversion efficiency (PCE) of single crystal-based solar cells is 21.9%, falling behind that of polycrystalline thin film solar cells (25.2%). The oversized thickness, defective surfaces, and difficulties in depositing functional layers, hinder the application of halide perovskite single crystals in optoelectronic devices. Efforts have been made to synthesize large-area single crystalline thin films directly on conductive substrates and apply defect engineering approaches to improve the surface properties. This review starts from a comprehensive introduction of the optoelectrical properties of perovskite single crystals. Then, the synthesis methods for high-quality bulk crystals and single-crystalline thin films are introduced and compared, followed by a systematic review of their optoelectronic applications including solar cells, photodetectors, and X-ray detectors. The challenges and strategical approaches for high-performance applications are summarized at the end with a brief outlook on future work.
Publisher: Wiley
Date: 11-09-2018
Publisher: Royal Society of Chemistry (RSC)
Date: 2011
DOI: 10.1039/C1CP20412B
Abstract: Tungsten oxide (WO(3)) electrodes subjected to a positive bias are self-photorecharged with alkali cations in the electrolyte during visible light illumination. Upon photoexcitation, part of the photogenerated charges generated by WO(3) is stabilized by the cations and stored in situ within the WO(3) framework. This light-induced storage of charges is subsequently utilized in dark conditions in an on-demand manner and is able to be recharged in the successive illumination cycles. The amount of charges stored is shown to be dependent on the cation ionic radii and the presence of these intercalated cations is verified by X-ray diffraction (XRD) and inductively coupled plasma mass spectroscopy (ICP-MS). This self-photorecharge and on-demand charge-release phenomena demonstrate the ability of WO(3) to supply photoexcited charges under dark condition in a photoelectrochemical reaction with greater flexibility.
Publisher: American Chemical Society (ACS)
Date: 08-01-2015
DOI: 10.1021/JA511615S
Abstract: Z-schematic water splitting was successfully demonstrated using metal sulfide photocatalysts that were usually unsuitable for water splitting as single particulate photocatalysts due to photocorrosion. When metal sulfide photocatalysts with a p-type semiconductor character as a H2-evolving photocatalyst were combined with reduced graphene oxide-TiO2 composite as an O2-evolving photocatalyst, water splitting into H2 and O2 in a stoichiometric amount proceeded. In this system, photogenerated electrons in the TiO2 with an n-type semiconductor character transferred to the metal sulfide through a reduced graphene oxide to achieve water splitting. Moreover, this system was active for solar water splitting.
Publisher: Wiley
Date: 03-03-2021
Publisher: Elsevier BV
Date: 11-2017
Publisher: American Chemical Society (ACS)
Date: 28-07-2022
Publisher: American Chemical Society (ACS)
Date: 13-04-2023
Publisher: Elsevier BV
Date: 09-2019
Publisher: Elsevier BV
Date: 06-2022
Publisher: Elsevier BV
Date: 02-2021
Publisher: Wiley
Date: 23-01-2017
Publisher: American Chemical Society (ACS)
Date: 13-04-2018
Publisher: Wiley
Date: 14-06-2021
Abstract: A direct thin film approach to fabricate large‐surface MoS 2 nanosheet thin film supercapacitors using the solution‐based diffusion of thiourea into an anodized MoO 3 thin film was investigated. A dense MoS 2 nanosheet thin film electrode (D‐MoS 2 ) was obtained when the anodized MoO 3 thin film was processed in a low thiourea solution concentration, whereas a highly porous MoS 2 nanosheet thin film electrode (P‐MoS 2 ) was formed at a higher thiourea solution concentration. The charge storage performances of the D‐MoS 2 and P‐MoS 2 thin films displayed an unusual increase in capacitance on extended cycling, leading to a capacitance as high as around 5–8 mF cm −2 . X‐ray diffraction and cross‐sectional microscopy revealed the capacitance enhancements of the MoS 2 supercapacitors are attributable to the nucleation of a new MoS 2‐ x O x phase upon cycling. For the D‐MoS 2 nanosheet thin film, the formation and growth of the MoS 2‐ x O x phase during cycling was accompanied by a volumetric expansion of the MoS 2 layer. For the P‐MoS 2 thin film, the nucleation and growth of the MoS 2‐ x O x phase occurred in the pores of the MoS 2 layer. The propagation of the MoS 2‐ x O x phase also shifted the charge storage process in both films from a diffusion‐limited process to a capacitive‐dominant process.
Publisher: Wiley
Date: 03-05-2018
Abstract: TiO
Publisher: Springer Science and Business Media LLC
Date: 30-11-2020
Publisher: American Chemical Society (ACS)
Date: 17-01-2019
Publisher: Elsevier BV
Date: 2007
Publisher: Elsevier BV
Date: 12-2019
Publisher: Elsevier BV
Date: 06-2019
Publisher: Wiley
Date: 28-07-2021
Abstract: Bismuth tungstate (Bi 2 WO 6 ) thin film photoanode has exhibited an excellent photoelectrochemical (PEC) performance when the tungsten (W) concentration is increased during the fabrication. Plate‐like Bi 2 WO 6 thin film with distinct particle sizes and surface area of different exposed facets are successfully prepared via hydrothermal reaction. The smaller particle size in conjunction with higher exposure extent of electron‐dominated {010} crystal facet leads to a shorter electron transport pathway to the bulk surface, assuring a lower charge transfer resistance and thus minimal energy loss. In addition, it is proposed based on the results from conductive atomic force microscopy that higher W concentration plays a crucial role in facilitating the charge transport of the thin film. The “self‐doped” of W in Bi 2 WO 6 will lead to the higher carrier density and improved conductivity. Thus, the variation in the W concentration during a synthesis can be served as a promising strategy for future W based photoanode design to achieve high photoactivity in water splitting application.
Publisher: American Chemical Society (ACS)
Date: 23-02-2018
Abstract: It has been reported that photogenerated electrons and holes can be directed toward specific crystal facets of a semiconductor particle, which is believed to arise from the differences in their surface electronic structures, suggesting that different facets can act as either photoreduction or photo-oxidation sites. This study examines the propensity for this effect to occur in faceted, plate-like bismuth molybdate (Bi
Publisher: American Chemical Society (ACS)
Date: 06-07-2010
DOI: 10.1021/CG100625M
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8TB00924D
Abstract: Discovering the distinctive photophysical properties of semiconductor nanoparticles (NPs) has made these a popular subject in recent advances in nanotechnology-related analytical methods.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7TA04441K
Abstract: This review summarises the recent advances of various strategies in improving the performances of BiVO 4 in photocatalytic and photoelectrochemical systems.
Publisher: Elsevier BV
Date: 12-2020
Publisher: Wiley
Date: 11-08-2008
Publisher: Elsevier BV
Date: 12-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0TA00629G
Abstract: An ultrathin amorphous ZnO layer is introduced on Cu 2 O by pulsed electrodeposition, which helps stabilise the Cu 2 O photocathode for water splitting.
Publisher: Wiley
Date: 10-07-2013
Publisher: American Chemical Society (ACS)
Date: 27-02-2012
DOI: 10.1021/JA211637P
Abstract: Opening up a band gap and finding a suitable substrate material are two big challenges for building graphene-based nanodevices. Using state-of-the-art hybrid density functional theory incorporating long-range dispersion corrections, we investigate the interface between optically active graphitic carbon nitride (g-C(3)N(4)) and electronically active graphene. We find an inhomogeneous planar substrate (g-C(3)N(4)) promotes electron-rich and hole-rich regions, i.e., forming a well-defined electron-hole puddle, on the supported graphene layer. The composite displays significant charge transfer from graphene to the g-C(3)N(4) substrate, which alters the electronic properties of both components. In particular, the strong electronic coupling at the graphene/g-C(3)N(4) interface opens a 70 meV gap in g-C(3)N(4)-supported graphene, a feature that can potentially allow overcoming the graphene's band gap hurdle in constructing field effect transistors. Additionally, the 2-D planar structure of g-C(3)N(4) is free of dangling bonds, providing an ideal substrate for graphene to sit on. Furthermore, when compared to a pure g-C(3)N(4) monolayer, the hybrid graphene/g-C(3)N(4) complex displays an enhanced optical absorption in the visible region, a promising feature for novel photovoltaic and photocatalytic applications.
Publisher: Elsevier BV
Date: 07-2017
DOI: 10.1016/J.JENVMAN.2017.03.078
Abstract: In this study, we have employed a photocatalytic method to restore the liquid effluent from a palm oil mill in Malaysia. Specifically, the performance of both TiO
Publisher: American Chemical Society (ACS)
Date: 08-03-2016
Abstract: Ambient fine particulate matter (PM) affects both human health and climate. To reduce the PM2.5 (mass of particles below 2.5 μm in diameter) concentration of an in idual's living environment, ionic liquid-modified polyacrylonitrile (PAN) nanofibers with superior PM2.5 capture capacity were prepared by electrospinning. Ionic liquid diethylammonium dihydrogen phosphate (DEAP) with high viscosity and hydrophilicity was involved during the electrospinning process. Observations by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and water contact angle measurement suggested that the modification of DEAP on PAN effectively altered the morphology (roughness) and surface properties (hydrophilicity) of the PAN nanofibers. The PM2.5 capture measurement was performed in a closed and static system, which mimicked the static hazy weather without wind flow. As a result, DEAP-modified PAN nanofibers exhibited significantly enhanced PM2.5 capture capacity compared to that of the bare PAN nanofibers. This can be attributed to the improved surface roughness (i.e., improved adsorption sites), hydrophilicity, and dipole moment of PAN upon DEAP modification.
Publisher: Springer Science and Business Media LLC
Date: 27-02-2017
Publisher: Springer Science and Business Media LLC
Date: 04-04-2018
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1MA00934F
Abstract: The photoactivity of rhombic dodecahedral Cu 2 O with dominant {110} facets is superior to that of cubic Cu 2 O with {100} surfaces partly owing to the improved charge separation and carrier mobility.
Publisher: Elsevier BV
Date: 2021
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C3RA45691A
Publisher: Elsevier BV
Date: 2021
Publisher: Elsevier BV
Date: 02-2015
Publisher: Wiley
Date: 02-07-2021
Publisher: American Chemical Society (ACS)
Date: 16-03-2012
DOI: 10.1021/JZ300179K
Abstract: We directly transformed anodized tungsten oxide film (WO3·2H2O) into bismuth tungstate (Bi2WO6) by substituting the intercalated water molecules with [Bi2O2](2+) in a hydrothermal treatment. The resultant Bi2WO6 was readily used as an electrode to produce anodic photocurrent in H2 evolution on the Pt counter electrode observed under visible light irradiation.
Publisher: American Chemical Society (ACS)
Date: 03-08-2016
DOI: 10.1021/JACS.6B05304
Abstract: Metal sulfides are highly active photocatalysts for water reduction to form H2 under visible light irradiation, whereas they are unfavorable for water oxidation to form O2 because of severe self-photooxidation (i.e., photocorrosion). Construction of a Z-scheme system is a useful strategy to split water into H2 and O2 using such photocorrosive metal sulfides because the photogenerated holes in metal sulfides are efficiently transported away. Here, we demonstrate powdered Z-schematic water splitting under visible light and simulated sunlight irradiation by combining metal sulfides as an H2-evolving photocatalyst, reduced graphene oxide (RGO) as an electron mediator, and a visible-light-driven BiVO4 as an O2-evolving photocatalyst. This Z-schematic photocatalyst composite is also active in CO2 reduction using water as the sole electron donor under visible light.
Publisher: Elsevier BV
Date: 07-2016
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7CY00246G
Abstract: Commercially available Sn foil was anodized in organic solvents to fabricate stable and cost-effective electrode that is demonstrated to convert CO 2 to formate with high selectivity.
Publisher: Elsevier BV
Date: 04-2019
Publisher: American Chemical Society (ACS)
Date: 02-02-2023
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C6TA10964K
Abstract: An increased presence of the {010} facet improved the performance of BiOBr for both water photooxidation and formic acid photodegradation.
Publisher: American Chemical Society (ACS)
Date: 09-01-2018
Publisher: Royal Society of Chemistry (RSC)
Date: 2012
DOI: 10.1039/C2EE22128D
Publisher: Elsevier BV
Date: 2021
Publisher: American Chemical Society (ACS)
Date: 19-06-2018
Publisher: Elsevier BV
Date: 05-2016
Publisher: American Chemical Society (ACS)
Date: 12-06-2009
DOI: 10.1021/JP903561Q
Publisher: American Chemical Society (ACS)
Date: 15-06-2020
Publisher: Elsevier BV
Date: 03-2019
Publisher: Elsevier BV
Date: 02-2020
Publisher: American Chemical Society (ACS)
Date: 30-08-2018
Publisher: American Chemical Society (ACS)
Date: 09-10-2023
Publisher: American Chemical Society (ACS)
Date: 03-09-2021
Publisher: Wiley
Date: 07-04-2023
Abstract: Selective photoelectrochemical (PEC) water oxidation to hydrogen peroxide is an underexplored option as opposed to the mainstream oxygen reduction reaction. Albeit interesting, selective H 2 O 2 production via oxidative pathway is plagued by the noncontrollable two‐electron transfer reaction and the overoxidation of the thus‐formed H 2 O 2 to O 2 . Here, ZnO passivator‐coated BiVO 4 photoanode is reported for selective PEC H 2 O 2 production. Both the H 2 O 2 selectivity and production rate increase in the range of 1.0–2.0 V versus RHE under simulated sunlight irradiation. The photoelectrochemical impedance spectra and open‐circuit potentials suggest a flattened band bending and positively shifted quasi‐Fermi level of BiVO 4 upon ZnO coating, facilitating H 2 O 2 generation and suppressing the competitive reaction of O 2 evolution. The ZnO overlayer also inhibits H 2 O 2 decomposition, accelerates charge extraction from BiVO 4 , and serves as a hole reservoir under photoexcitation. This work offers insights into surface states and the role of the coating layer in manipulating two/four‐electron transfer for selective H 2 O 2 synthesis from PEC water oxidation.
Publisher: Elsevier BV
Date: 06-2020
Publisher: Springer Science and Business Media LLC
Date: 10-10-2020
Publisher: Elsevier BV
Date: 08-2014
Publisher: American Chemical Society (ACS)
Date: 06-04-2016
Publisher: American Chemical Society (ACS)
Date: 04-12-2008
DOI: 10.1021/CM702034W
Publisher: Wiley
Date: 26-01-2016
Abstract: Efficient and low-cost electrocatalysts for water splitting are essential for solar fuel production. Herein, we report that nanoarrays of CoP supported on carbon cloth are an efficient bifunctional catalyst for overall water splitting. The catalyst exhibits remarkable activity for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline media, delivering a current density of 10 mA cm(-2) at an overpotential of 281 mV for OER and 95 mV for HER. During electrocatalysis, the surface of the CoP catalyst was covered with a layer of CoOx , which was the active species. However, the CoP core and the nanoarray morphology contributed significantly to the activity.
Publisher: American Chemical Society (ACS)
Date: 21-04-2016
Abstract: Some oxides have the ability to trap excess electrons in the form of small polarons. Here, using first-principles techniques, we investigate the interaction of excess electrons with α-MoO3. Polarons are found to be about 0.6 eV more stable than delocalized electrons. They can propagate with a high degree of anisotropicity along different crystallographic directions with the lowest barrier found to be about 0.08 eV. In addition to the band gap photoexcited charge carriers that can populate such polaron states, we investigate the role of oxygen vacancies as an intrinsic source of electrons. We also investigate intercalated alkali ions that can form complexes with the created polarons in the lattice. The alkali-polaron complex (AxMoO6, A = alkali ion) binding energies are relatively low, making it easy for the complex to dissociate. This, coupled with the low polaron migration energies, can generate a non-negligible contribution to electronic conductivity even in the absence of illumination, which is experimentally verified. Combined, this light-induced intercalation of alkali ion in MoO3 and its subsequent deintercalation (complex dissociation) processes lead to a novel self-photocharghing phenomenon.
Publisher: American Chemical Society (ACS)
Date: 20-05-2016
DOI: 10.1021/ACS.CHEMREV.6B00075
Abstract: As a fascinating conjugated polymer, graphitic carbon nitride (g-C3N4) has become a new research hotspot and drawn broad interdisciplinary attention as a metal-free and visible-light-responsive photocatalyst in the arena of solar energy conversion and environmental remediation. This is due to its appealing electronic band structure, high physicochemical stability, and "earth-abundant" nature. This critical review summarizes a panorama of the latest progress related to the design and construction of pristine g-C3N4 and g-C3N4-based nanocomposites, including (1) nanoarchitecture design of bare g-C3N4, such as hard and soft templating approaches, supramolecular preorganization assembly, exfoliation, and template-free synthesis routes, (2) functionalization of g-C3N4 at an atomic level (elemental doping) and molecular level (copolymerization), and (3) modification of g-C3N4 with well-matched energy levels of another semiconductor or a metal as a cocatalyst to form heterojunction nanostructures. The construction and characteristics of each classification of the heterojunction system will be critically reviewed, namely metal-g-C3N4, semiconductor-g-C3N4, isotype g-C3N4/g-C3N4, graphitic carbon-g-C3N4, conducting polymer-g-C3N4, sensitizer-g-C3N4, and multicomponent heterojunctions. The band structures, electronic properties, optical absorption, and interfacial charge transfer of g-C3N4-based heterostructured nanohybrids will also be theoretically discussed based on the first-principles density functional theory (DFT) calculations to provide insightful outlooks on the charge carrier dynamics. Apart from that, the advancement of the versatile photoredox applications toward artificial photosynthesis (water splitting and photofixation of CO2), environmental decontamination, and bacteria disinfection will be presented in detail. Last but not least, this comprehensive review will conclude with a summary and some invigorating perspectives on the challenges and future directions at the forefront of this research platform. It is anticipated that this review can stimulate a new research doorway to facilitate the next generation of g-C3N4-based photocatalysts with ameliorated performances by harnessing the outstanding structural, electronic, and optical properties for the development of a sustainable future without environmental detriment.
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6TA00700G
Abstract: A photoactive Bi 2 MoO 6 /MoO 3 heterojunction electrode derived from a direct thin-film-route showed close to 100% faradic photocurrent-to-O 2 conversion efficiency.
Publisher: Wiley
Date: 25-03-2019
Publisher: Springer Science and Business Media LLC
Date: 20-10-2022
DOI: 10.1038/S41467-022-33905-6
Abstract: Metal oxides are promising for photoelectrochemical (PEC) water splitting due to their robustness and low cost. However, poor charge carrier transport impedes their activity, particularly at low-bias voltage. Here we demonstrate the unusual effectiveness of phosphorus doping into bismuth vanadate (BiVO 4 ) photoanode for efficient low-bias PEC water splitting. The resulting BiVO 4 photoanode shows a separation efficiency of 80% and 99% at potentials as low as 0.6 and 1.0 V RHE , respectively. Theoretical simulation and experimental analysis collectively verify that the record performance originates from the unique phosphorus-doped BiVO 4 configuration with concurrently mediated carrier density, trap states, and small polaron hopping. With NiFeO x cocatalyst, the BiVO 4 photoanode achieves an applied bias photon-to-current efficiency of 2.21% at 0.6 V RHE . The mechanistic understanding of the enhancement of BiVO 4 properties provides key insights in trap state passivation and polaron hopping for most photoactive metal oxides.
Publisher: Wiley
Date: 06-08-2023
Abstract: Hydrogen peroxide is an essential chemical that is attracting strong attention for energy and environmental applications. However, the struggle between the growing market demand and the unsustainability of the conventional anthraquinone method motivates the exploration of alternative H 2 O 2 production processes. Although several new production processes have been proposed, the environmental‐friendly solar‐driven H 2 O 2 production attracts most attention because of the only inputs of water, oxygen, and light energy. The rational design of functional photo‐responsive catalysts promotes H 2 O 2 production in the photocatalytic and photoelectrocatalytic approaches. These are, in general, achieved by facilitating the preferential adsorption of key intermediates of OOH*/OH*/O*, enhancing the light absorption, promoting the charge separation, and accelerating the surface charge transfer with selective number of involved charges. This review systematically summarizes strategies for photo(electro)catalysts toward H 2 O 2 production via both the water oxidation and oxygen reduction pathways. Though the oxygen reduction route is perceived as more popular in the community, selective water oxidation is emerging as a convincing alternative. Furthermore, prevailing hypotheses, state‐of‐the‐art catalysts, critical challenges, and perspectives are discussed in depth. This review aims to enhance the comprehension of this research field and promote interest in sustainable H 2 O 2 production.
Publisher: Elsevier BV
Date: 05-2020
Publisher: American Chemical Society (ACS)
Date: 24-09-2021
Publisher: Royal Society of Chemistry (RSC)
Date: 30-06-2014
DOI: 10.1039/C4NR01175A
Abstract: The preparation of hybrid hollow capsules consisting of a cross-linked polymer shell and a coating of graphene oxide (GO) is demonstrated. The capsules are prepared by Pickering miniemulsion polymerization, exploiting the surface activity of GO for its use as a colloidal surfactant. This approach represents a simple and convenient route towards hollow carbon nanostructures for a variety of applications. The incorporation of surface-modified TiO2 nanoparticles into the interior of these capsules was also demonstrated.
Publisher: American Chemical Society (ACS)
Date: 28-05-2019
Abstract: Optimizing interfacial contact between graphene and a semiconductor has often been proposed as essential for improving their charge interactions. Herein, we fabricated bismuth vanadate-reduced graphene oxide (BiVO
Publisher: Wiley
Date: 16-10-2008
Publisher: MDPI AG
Date: 20-12-2022
DOI: 10.3390/EN16010027
Abstract: Nitrogen reduction reaction (NRR) and nitrate reduction reaction (NO3−RR) provide a potential sustainable route by which to produce ammonia, a next-generation energy carrier. Many studies have been conducted over the years, mainly emphasizing material design and strategies to improve catalytic performance. Despite significant achievements in material design and corresponding fundamental knowledge, the produced ammonia is still very limited, which makes it prone to bias. The presence of interferants (e.g., cations and sacrificial reagents), the pH of the solution, and improper analytical procedure can lead to the over or underestimation of ammonia quantification. Therefore, the selection of the appropriate ammonia quantification method, which meets the s le solution condition, along with the proper analytical procedures, is of great importance. In this review, the state-of-the-art ammonia quantification method is summarized, emphasizing the advantages, limitations, and practicality for NRR and NO3−RR studies. Fundamental knowledge of the quantification method is introduced. Perspective on the considerations for selecting the suitable quantification method and for performing the quantification process is also provided. Although non exhaustive, this focused review can be useful as a guide to design the experimental setup and procedure for more reliable ammonia quantification results.
Publisher: Elsevier BV
Date: 03-2018
Publisher: American Chemical Society (ACS)
Date: 14-01-2020
Abstract: Metal and metal-oxide particles are commonly photodeposited on photocatalysts by reduction and oxidation reactions, respectively, consuming charges that are generated under illumination. This study reveals that amorphous MoO
Publisher: Elsevier BV
Date: 10-2015
Publisher: Elsevier BV
Date: 08-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8EE00976G
Abstract: The facile and scalable synthesis of manganese-doped nickel/nickel oxide heterostructures with high activity, outperforming the Pt benchmark, in neutral electrolytes.
Publisher: Wiley
Date: 05-09-2019
Publisher: American Chemical Society (ACS)
Date: 03-06-2013
DOI: 10.1021/AM401112Q
Abstract: The current work demonstrates the importance of WO3 crystallinity in governing both photoenergy conversion efficiency and storage capacity of the flower structured WO3 electrode. The degree of crystallinity of the WO3 electrodes was varied by altering the calcination temperature from 200 to 600 °C. For the self-photochargeability phenomenon, the prevailing flexibility of the short-range order structure at low calcination temperature of 200 °C favors the intercalation of the positive cations, enabling more photoexcited electrons to be stored within WO3 framework. This leads to a larger amount of stored charges that can be discharged in an on-demand manner under the absence of irradiation for H2 generation. The stability of the electrodes calcined at 200 °C, however, is compromised because of the structural instability caused by the abundance insertion of cations. On the other hand, films that were calcined at 400 °C displayed the highest stability toward both intercalation of the cations and photoelectrochemical water splitting performance. Although crystallinty of WO3 was furthered improved at 600 °C heat treatment, the worsened contact between the WO3 platelets and the conducting substrate as induced by the significant sintering has been more detrimental toward the charge transport.
Publisher: Wiley
Date: 15-10-2021
Abstract: Ammonia (NH 3 ) plays a vital role in the fertilizer industry, nitrogen‐containing chemical production, and hydrogen storage. The development of electrocatalytic and photo(electro)catalytic nitrogen reduction reaction (NRR) to synthesize NH 3 are desirable, which are more environmentally friendly than the conventional Haber–Bosch process. Due to the strong nonpolar bonding of the NN bond, the discovery of efficient catalysts is essential to overcome the high kinetic barrier. Here, bismuth‐based materials that show proven activities for NRR are highlighted. The fundamental knowledge, including thermodynamics, mechanisms, reaction systems, evaluation aspects of NRR, and product quantification, is introduced. Together with scientific reasoning and exhibited activities, the strategies for improving the performance are discussed in detail. Perspective and outlook, as well as the opportunities to further develop bismuth‐based materials for NH 3 synthesis, are provided. This review aims to provide a comprehensive understanding of the advancement in this field and serves as a guide for the future design of highly efficient NRR catalysts.
Publisher: Wiley
Date: 10-11-2017
Abstract: Rising levels of CO
Publisher: Wiley
Date: 08-05-2014
Abstract: Nanostructured molybdenum oxide (α-MoO3 ) thin film photoelectrodes were synthesised by anodisation. Upon band gap-excitation by light illumination, α-MoO3 is able to store a portion of the excited charges in its layered structure with the simultaneous intercalation of alkali cations. The stored electrons can be discharged from α-MoO3 for utilisation under dark conditions, and α-MoO3 is able to recharge itself with successive illuminations to behave as a 'self-photo-rechargeable' alkali-ion battery. The alteration of the anodisation pH allowed the crystal structure and oxygen vacancy concentrations of α-MoO3 to be modulated to achieve (i) a distorted MoO6 octahedra for enhanced charge separation and storage, (ii) a layered structure with a greater exposed (010) crystal face for rich and reversible ion intercalation and (iii) a highly crystalline thin film that suppresses electron-hole pair recombination. Overall, the larger MoO6 octahedral distortion in α-MoO3 at a higher pH favours charge storage, whereas smaller octahedral distortion at a lower pH leads to anodic photocurrent enhancement.
Publisher: Wiley
Date: 11-12-2013
Abstract: Gold nanoparticles incorporated in mesoporous cobalt oxides (Au/mCo3 O4 ) are fabricated by a nanocasting method using porous silica as the hard template. The Au/mCo3 O4 material exhibits enhanced catalytic activity towards water oxidation compared to bulk mCo3 O4 in both alkaline and neutral solutions. The superior catalytic performance is ascribed to the synergistic effect of electronegative metal gold, which facilitates the generation of active Co(IV) sites, as well as the large specific surface area and the preferential exposure of catalytic active crystalline lattice.
Publisher: Elsevier BV
Date: 08-2016
Publisher: Royal Society of Chemistry (RSC)
Date: 2011
DOI: 10.1039/C1CC13159A
Abstract: We demonstrate a general strategy to prepare Bi(2)WO(6)/Ag/N-TiO(2) film with double visible-light-active components bridged by Ag nanoparticles as an electron shuttle, which exhibits enhanced photocatalytic activity and photoelectrochemical performance under visible light.
Publisher: American Chemical Society (ACS)
Date: 18-02-2016
Publisher: Elsevier BV
Date: 09-2020
Publisher: American Chemical Society (ACS)
Date: 06-07-2011
DOI: 10.1021/JA203296Z
Abstract: The effectiveness of reduced graphene oxide as a solid electron mediator for water splitting in the Z-scheme photocatalysis system is demonstrated. We show that a tailor-made, photoreduced graphene oxide can shuttle photogenerated electrons from an O(2)-evolving photocatalyst (BiVO(4)) to a H(2)-evolving photocatalyst (Ru/SrTiO(3):Rh), tripling the consumption of electron-hole pairs in the water splitting reaction under visible-light irradiation.
Publisher: Elsevier BV
Date: 03-2017
Publisher: Springer Science and Business Media LLC
Date: 11-12-2014
DOI: 10.1038/SREP07428
Abstract: Nanocrystalline molybdenum oxide (α-MoO 3 ) thin films with iso-oriented crystalline layers were synthesised by the anodisation of Mo foils. Upon band-gap excitation using light illumination, α-MoO 3 generates excited electrons for reductive reactions and stores some of the excited electrons in its layered crystalline structure via alkali cation intercalation. These stored electrons can be subsequently discharged from α-MoO 3 to allow reductive reactions to continue to occur under non-illuminated conditions. The modulation of water concentrations in the organic/aqueous anodisation electrolytes readily produces α-MoO 3 crystals with high degree of (kk0) crystallographic orientation. Moreover, these (kk0)-oriented MoO 3 crystals exhibit well-developed {hk0} and {0k0} crystal facets. In this paper, we show the benefits of producing α-MoO 3 thin films with defined crystal facets and an iso-oriented layered structure for in situ storing of excited charges. α-MoO 3 crystals with dominant (kk0) planes can achieve fast charging and a strong balance between charge release for immediate exploitation under illuminated conditions and charge storage for subsequent utilisation in dark. In comparison, α-MoO 3 crystals with dominant (0k0) planes show a preference for excited charge storage.
Publisher: Wiley
Date: 04-07-2019
Start Date: 2011
End Date: 2013
Funder: Australian Research Council
View Funded ActivityStart Date: 2017
End Date: 2017
Funder: Australian Academy of Science
View Funded ActivityStart Date: 2017
End Date: 2017
Funder: Australian Research Council
View Funded ActivityStart Date: 2017
End Date: 2019
Funder: Australian Research Council
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