ORCID Profile
0000-0003-3236-7168
Current Organisation
Beijing Technology and Business University
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Publisher: Elsevier BV
Date: 12-2018
DOI: 10.1016/J.IJBIOMAC.2018.09.204
Abstract: Starch molecular structure, in terms of chain-length distribution (CLD) and molecular size, are important structural features regarding to "(starch) structure-property" relations for starch-based foods. In this study, amylopectin CLDs from fluorophore-assisted carbohydrate electrophoresis (FACE) are parameterized by a biosynthesis-based model, amylose CLDs and molecular sizes of amylose and amylopectin are measured by size-exclusion chromatography (SEC), and statistically meaningful relationships are established between starch CLDs, starch molecular size, and amylose content using rice starches with a wide range of amylose content. This shows that amylopectin molecular size is increased by increasing the proportion of short amylopectin chains with degree of polymerization (DP) 6-32 and decreasing the percentage of long amylopectin chains with DP 63-100. On the other hand, molecular sizes of both branched amylopectin and amylose molecules are negatively correlated with amylose content, suggesting that high-amylose rice tends to have smaller amylopectin and amylose molecular sizes. These relations are rationalized in terms of chain-length effects on the production of branched amylopectin and amylose molecules between different rice cultivars, which could provide new insights regarding to starch "structure-property" relations.
Publisher: Springer Science and Business Media LLC
Date: 26-03-2014
Publisher: American Chemical Society (ACS)
Date: 10-07-2018
Abstract: The copper nanoflowers, assembled by sub-2 nm rough nanowires with high catalytic active (200) facets, are prepared by a prompt and simple method with cetyltrimethylammonium bromide (CTAB) as a capping agent. The CTAB plays a vital role in the synthesis process, whereas the copper nanorod arrays assembled by copper nanoparticles are obtained without CTAB. The copper nanoflowers are used as catalysts in oxygen reduction reactions and exhibit excellent electrocatalytic activity, which shows nearly the same activity compared with the commercial Pt/C catalyst, attributing to the nanoflower-exposed higher catalytic active (200) facets. Furthermore, the nanoflowers can avoid methanol-poison effect and show better long-term operation stability. The density functional theory was used to calculate the atom energy of Cu(100) facets and Cu(111) facets. Both of O
Publisher: Royal Society of Chemistry (RSC)
Date: 2009
DOI: 10.1039/B915838C
Publisher: Wiley
Date: 07-11-2015
Abstract: Phosphorus-doped (P-doped) graphene with the P doping level of 1.30 at % was synthesized by annealing the mixture of graphene and phosphoric acid. The presence of P was confirmed by elemental mapping and X-ray photoelectron spectroscopy, while the morphology of P-doped graphene was revealed by using scanning electron microscopy and transmission electron microscopy. To investigate the effect of P doping, the electrochemical properties of P-doped graphene were tested as a supercapacitor electrode in an aqueous electrolyte of 1 M H2 SO4. The results showed that doping of P in graphene exhibited significant improvement in terms of specific capacitance and cycling stability, compared with undoped graphene electrode. More interestingly, the P-doped graphene electrode can survive at a wide voltage window of 1.7 V with only 3 % performance degradation after 5000 cycles at a current density of 5 A g(-1), providing a high energy density of 11.64 Wh kg(-1) and a high power density of 831 W kg(-1).
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9RA01330J
Abstract: A novel FeNC/MXene hybrid nanosheet with a rugged FeNC coating closely attached on the MXene surface was explored, which exhibited remarkable electrocatalytic activity with a superb durability (only 2.6% decay after a 20 000 s continuous test).
Publisher: American Chemical Society (ACS)
Date: 28-03-2019
Publisher: Elsevier BV
Date: 03-2021
Publisher: American Chemical Society (ACS)
Date: 08-01-2020
DOI: 10.1021/ACS.INORGCHEM.9B03370
Abstract: The hexagonal copper-tin alloy (Cu-Sn) nanoplates were synthesized using a high temperature solvent method, the length of six equilateral edges of hexagonal Cu-Sn nanoplates was 23 nm, and the thickness was 13 nm. The obtained hexagonal Cu-Sn nanoplates were highly monodisperse and allowed the formation of nanoarrays arranged with long-range order. The hexagonal Cu-Sn nanoplates exhibited high catalytic activity on catalytic hydrogenation of 4-nitrophenol to 4-aminophenol. Due to the promotion effect of Sn, the apparent rate constant (
Publisher: MDPI AG
Date: 20-05-2019
DOI: 10.3390/NANO9050775
Abstract: Oxygen evolution reaction (OER) is a pivotal step for many sustainable energy technologies, and exploring inexpensive and highly efficient electrocatalysts is one of the most crucial but challenging issues to overcome the sluggish kinetics and high overpotentials during OER. Among the numerous electrocatalysts, metal-organic frameworks (MOFs) have emerged as promising due to their high specific surface area, tunable porosity, and ersity of metal centers and functional groups. It is believed that combining MOFs with conductive nanostructures could significantly improve their catalytic activities. In this study, an MXene supported CoNi-ZIF-67 hybrid (CoNi-ZIF-67@Ti3C2Tx) was synthesized through the in-situ growth of bimetallic CoNi-ZIF-67 rhombic dodecahedrons on the Ti3C2Tx matrix via a coprecipitation reaction. It is revealed that the inclusion of the MXene matrix not only produces smaller CoNi-ZIF-67 particles, but also increases the average oxidation of Co/Ni elements, endowing the CoNi-ZIF-67@Ti3C2Tx as an excellent OER electrocatalyst. The effective synergy of the electrochemically active CoNi-ZIF-67 phase and highly conductive MXene support prompts the hybrid to process a superior OER catalytic activity with a low onset potential (275 mV vs. a reversible hydrogen electrode, RHE) and Tafel slope (65.1 mV∙dec−1), much better than the IrO2 catalysts and the pure CoNi-ZIF-67. This work may pave a new way for developing efficient non-precious metal catalyst materials.
Publisher: Elsevier BV
Date: 12-2017
Publisher: American Chemical Society (ACS)
Date: 09-08-2019
Publisher: Elsevier BV
Date: 12-2021
Publisher: MDPI AG
Date: 10-08-2019
DOI: 10.3390/NANO9081147
Abstract: The metal halide with a perovskite structure has attracted significant attention due to its defect-tolerant photophysics and optoelectronic features. In particular, the all-inorganic metal halide perovskite quantum dots have potential for development in future applications. Sub-2 nm CsPbX3 (X = Cl, Br, and I) perovskite quantum dots were successfully fabricated by a MOF-confined strategy with a facile and simple route. The highly uniform microporous structure of MOF effectively restricted the CsPbX3 quantum dots aggregation in a synthetic process and endowed the obtained sub-2 nm CsPbX3 quantum dots with well-dispersed and excellent stability in ambient air without a capping agent. The photoluminescence emission spectra and lifetimes were not decayed after 60 days. The CsPbX3 quantum dots maintained size distribution stability in the air without any treatment. Because of the quantum confinement effect of CsPbX3 quantum dots, the absorption and photoluminescence (PL) emission peak were blue shifted to shorter wavelengths compare with bulk materials. Furthermore, this synthetic strategy provides a novel method in fabricating ultra-small photoluminescence quantum dots.
Publisher: Royal Society of Chemistry (RSC)
Date: 2013
DOI: 10.1039/C2NR32735J
Abstract: Carbon nanotubes (CNTs) and graphene (GNS) hybrid multiple-thread yarns were fabricated by chemical vapor deposition followed by a posted-stretching processing. The as-prepared CNTs and GNS multiple-thread yarns consisted of tens of single-thread fibers with diameters of around 20 μm. The single-thread fibers are composed of double-walled carbon nanotube (DWNT) bundles and GNS tablets. DWNT bundles in the single-thread fiber are highly disordered and are rounded by GNS. The content and dimensions of GNS are changeable along the fiber axial direction. The as-obtained CNT and GNS hybrid multiple-thread yarns can be twisted, forming one fiber. The mechanical measurement of the twisted yarn gave a strength of 300 MPa and the electrical conductivity is 10(5) S m(-1). These unique structures, possessing various promising properties, can be readily and directly applied in different fields. Here, the hybrid yarns of CNTs and GNS were applied as a l thread and woven macroscopic body, as demonstrated.
Publisher: Wiley
Date: 02-02-2016
Abstract: The co-doping of heteroatoms has been regarded as a promising approach to improve the energy-storage performance of graphene-based materials because of the synergetic effect of the heteroatom dopants. In this work, a single precursor melamine phosphate was used for the first time to synthesise nitrogen hosphorus co-doped graphene (N/P-G) monoliths by a facile hydrothermal method. The nitrogen contents of 4.27-6.58 at% and phosphorus levels of 1.03-3.00 at% could be controlled by tuning the mass ratio of melamine phosphate to graphene oxide in the precursors. The N/P-G monoliths exhibited excellent electrochemical performances as electrodes for supercapacitors with a high specific capacitance of 183 F g(-1) at a current density of 0.05 A g(-1), good rate performance and excellent cycling performance. Additionally, the N/P-G electrode was stable at 1.6 V in 1 m H2 SO4 aqueous electrolyte and delivered a high energy density of 11.33 Wh kg(-1) at 1.6 V.
Publisher: American Chemical Society (ACS)
Date: 05-12-2019
Publisher: American Chemical Society (ACS)
Date: 06-07-2016
Abstract: Nitrogen-rich graphene nanosheets (NGN) with intentionally crumpled, stacked, and cross-linked sheet structures were developed using hydrothermal and/or formaldehyde polymerization processes. It is revealed that the hydrothermal treatment produced crumpled NGN (6.0 at% N) with a high surface area of 383 m(2)·g(-1). In contrast, the formaldehyde polymerization process yielded stacked NGN (11.3 at% N) with very low surface area. The combination of formaldehyde polymerization synthesis with hydrothermal treatment led to NGN (14.7 at% N) with a cross-linked structure and a moderate surface area of 88 m(2)·g(-1). Interestingly, this cross-linked NGN exhibited the best electrochemical performance compared with other NGN, with a remarkable specific capacitance of 201 F·g(-1) at 0.05 A·g(-1) in 1 M H2SO4 electrolyte, and an excellent retention rate of 96.2% of the initial capacitance after 10 000 charge-discharge cycles at a current density of 5 A·g(-1) was achieved.
Publisher: Elsevier BV
Date: 2021
Publisher: Royal Society of Chemistry (RSC)
Date: 2013
DOI: 10.1039/C3CP44085K
Abstract: A carbon-nanotube (CNT)/silver olymer composite fiber was fabricated using carbon nanotube fiber (CNTF) to infiltrate silver-paste liquid for effective reinforcement of electrical conductivity and strength of the CNT fibers. The as-obtained composite fiber is still flexible with a content of 43 wt% CNTs. Scanning electronic microscopy (SEM) observation shows that the silver-paste layer covering on the surface of the CNTF and polymer infiltrated into the CNTFs. The electrical conductivity and strength of the achieved composite fiber were effectively improved. Mechanical measurement of the composite fiber gave a strength of 940 MPa, 2.7 times that of a reference CNTF. The electrical conductivity of the composite fiber is 5.0 × 10(5) S m(-1), 2.6 times that of the referenced CNTF. Additionally, through control of the fabrication process, a coaxial fiber comprising a silver-paste "tube" and pure CNT fiber can be achieved. This route for making composite fibers is easy and controllable, apt for development of high-performance fibers.
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8TC02156B
Abstract: Quantum dots, derived from two-dimensional (2D) materials, have shown promising applications in bioimaging, photocatalysis, biosensors and white light emission devices (W-LEDs).
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C7TA09493K
Abstract: A ruthenium-doped, collagen-based carbon scaffold (Ru-CCS), as a highly efficient electrocatalyst for the HER, is achieved via a biomimetic approach.
Publisher: Royal Society of Chemistry (RSC)
Date: 2012
DOI: 10.1039/C2NR30318C
Abstract: An electrically conductive and electrochemically active composite paper of graphene nanosheet (GNS) coated cellulose fibres was fabricated via a simple paper-making process of dispersing chemically synthesized GNS into a cellulose pulp, followed by infiltration. The GNS nanosheet was deposited onto the cellulose fibers, forming a coating, during infiltration. It forms a continuous network through a bridge of interconnected cellulose fibres at small GNS loadings (3.2 wt%). The GNS/cellulose paper is as flexible and mechanically tough as the pure cellulose paper. The electrical measurements show the composite paper has a sheet resistance of 1063 Ω□(-1) and a conductivity of 11.6 S m(-1). The application of the composite paper as a flexible double layer supercapacitor in an organic electrolyte (LiPF(6)) displays a high capacity of 252 F g(-1) at a current density of 1 A g(-1) with respect to GNS. Moreover, the paper can be used as the anode in a lithium battery, showing distinct charge and discharge performances. The simple process for synthesising the GNS functionalized cellulose papers is attractive for the development of high performance papers for electrical, electrochemical and multifunctional applications.
Publisher: Elsevier BV
Date: 08-2017
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