ORCID Profile
0000-0003-4847-2907
Current Organisation
University of Wollongong
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Elsevier BV
Date: 11-2021
Publisher: Wiley
Date: 16-08-2023
Abstract: Magnonics or magnon spintronics is an emerging field focusing on generating, detecting, and manipulating magnons. As charge‐neutral quasi‐particles, magnons are promising information carriers because of their low energy dissipation and long coherence length. In the past decade, topological phases in magnonics have attracted intensive attention due to their fundamental importance in condensed‐matter physics and potential applications of spintronic devices. In this review, we mainly focus on recent progress in topological magnonics, such as the Hall effect of magnons, magnon Chern insulators, topological magnon semimetals, etc. In addition, the evidence supporting topological phases in magnonics and candidate materials are also discussed and summarized. The aim of this review is to provide readers with a comprehensive and systematic understanding of the recent developments in topological magnonics.
Publisher: Elsevier BV
Date: 12-2022
Publisher: Wiley
Date: 29-09-2020
Publisher: Springer Science and Business Media LLC
Date: 18-05-2023
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0TA00227E
Abstract: Recent advances in smart textiles and wearable technologies based on piezoelectric fibers as wearable energy harvesters.
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9CP01981B
Abstract: Magnetism in two-dimensional (2D) materials, that is, a 2D version of the magnetism of three-dimensional bulk materials, and the associated novel physics have recently been the focus of many spintronics researchers. Here we investigate the manipulation of 2D magnetism at the interfaces of ferromagnetic/ferroelectric hematene/BaTiO
Publisher: American Chemical Society (ACS)
Date: 16-08-2023
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0RA01425G
Abstract: An efficient thermal-treatment method was developed for the preparation of defect modified g-C 3 N 4 with excellent photocatalytic H 2 production performance.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0TC00504E
Abstract: In this study, via first-principles, we predict that a recently synthesized BaLi 2 Sn material with Pmmn structure is a TNLS with perfect intersecting nodal rings in the k x = 0 and k y = 0 planes when the spin–orbit coupling (SOC) effect is ignored.
Publisher: AIP Publishing
Date: 04-11-2022
DOI: 10.1063/5.0095281
Abstract: The topological phenomenon has been extensively studied in condensed matter physics and has attracted much attention in many different fields. Like electrons, phonons can also be studied using critical theorems and topology concepts, giving impetus to the birth of topological phonons. Among the topological phonons, the topological nodal line phonons in crystalline materials have emerged as a new area of rapid development in both experiment and theory. Researchers have been hunting for realistic materials with nodal line phonons for the last four years. To date, however, a timely review of recent advances in topological nodal line phonons, and especially their material realization, is still lacking. Considering the classification of the nodal line states, in this review, we will first review the identification of the materials hosting the nodal line phonons with different degeneracies, different types of dispersion, and different geometric shapes in theory. Moreover, we will review and discuss the reasons for the appearance of the nodal line phonons from the viewpoint of symmetry. Second, we will review the case where the nodal line appears in the projected surface phonon states instead of the bulk phonon states. Third, we will review the experimental material realization of nodal line phonons. Finally, we will present a summary, outlook, and additional notes. We believe that this review will contribute to a more advanced understanding of topological nodal line phonons in solid materials and will offer new perspectives on this rapidly expanding field.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0TC02024A
Abstract: Diverse topological states are identified in the ternary compound NdAsPd.
Publisher: American Physical Society (APS)
Date: 13-07-2020
Publisher: Springer Science and Business Media LLC
Date: 23-11-2020
DOI: 10.1038/S41467-020-19779-6
Abstract: Atom-thick van der Waals heterostructures with nontrivial physical properties tunable via the magnetoelectric coupling effect are highly desirable for the future advance of multiferroic devices. In this work on LaCl/In 2 Se 3 heterostructure consisting of a 2D ferromagnetic layer and a 2D ferroelectric layer, reversible switch of the easy axis and the Curie temperature of the magnetic LaCl layer has been enabled by switching of ferroelectric polarization in In 2 Se 3 . More importantly, magnetic skyrmions in the bimerons form have been discovered in the LaCl/In 2 Se 3 heterostructure and can be driven by an electric current. The creation and annihilation of bimerons in LaCl magnetic nanodisks were achieved by polarization switching. It thus proves to be a feasible approach to achieve purely electric control of skyrmions in 2D van der Waals heterostructures. Such nonvolatile and tunable magnetic skyrmions are promising candidates for information carriers in future data storage and logic devices operated under small electrical currents.
Publisher: Wiley
Date: 22-10-2020
DOI: 10.1111/JACE.16844
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0CY01727B
Abstract: In situ synthesized Ru-doped FeCoP nanoarray electrocatalysts with high activity and stability for overall water splitting.
Publisher: Springer Science and Business Media LLC
Date: 05-11-2021
DOI: 10.1038/S41427-021-00338-4
Abstract: Materials exhibiting zero thermal expansion (ZTE), namely, volume invariance with temperature change, can resist thermal shock and are highly desired in modern industries for high-precision components. However, pure ZTE materials are rare, especially those that are metallic. Here, we report the discovery of a pure metallic ZTE material: an orthorhombic Mn 1- x Ni x CoSi spiral magnet. The introduction of Ni can efficiently enhance the ferromagnetic exchange interaction and construct the transition from a spiral magnetic state to a ferromagnetic-like state in MnCoSi-based alloys. Systematic in situ neutron powder diffraction revealed a new cycloidal spiral magnetic structure in the bc plane in the ground state, which transformed to a helical spiral in the ab plane with increasing temperature. Combined with Lorentz transmission electron microscopy techniques, the cycloidal and helical spin order coherently rotated at varying periods along the c -axis during the magnetic transition. This spin rotation drove the continuous movement of the coupled crystalline lattice and induced a large negative thermal expansion along the a -axis, eventually leading to a wide-temperature ZTE effect. Our work not only introduces a new ZTE alloy but also presents a new mechanism by which to discover or design ZTE magnets.
Publisher: Elsevier BV
Date: 12-2022
Publisher: American Physical Society (APS)
Date: 25-05-2023
Publisher: AIP Publishing
Date: 15-02-2021
DOI: 10.1063/5.0039842
Abstract: Two-dimensional (2D) multiferroics attract intensive investigations because of underlying science and their potential applications. Although many 2D systems have been observed redicted to be ferroelectric or ferromagnetic, 2D materials with both ferroic properties are still scarce. By using first-principles calculations, we predict that hole-doping can induce robust ferromagnetism in 2D ferroelectric α-In2Se3 due to its unique flatband structure, and the Curie temperature (TC) can be much higher than room temperature. Moreover, the doping concentration, strain, and number of layers can effectively modulate the magnetic moment and TC of the material. Interestingly, strong magnetoelectric coupling is found at the surface of hole doped multilayer α-In2Se3, which allows nonvolatile electric control of magnetization. Our work provides a feasible approach for designing/searching 2D multiferroics with great potential in future device applications, such as memory devices and sensors.
Publisher: Elsevier BV
Date: 04-2023
Publisher: American Chemical Society (ACS)
Date: 13-09-2023
Publisher: Research Square Platform LLC
Date: 05-04-2021
DOI: 10.21203/RS.3.RS-361418/V1
Abstract: To reach a closed-loop material system and meet the urgent requirement of sustainable energy storage technologies, it is essential to incorporate efficient waste management into designing new energy storage materials. Here, we reported a “two birds with one stone” strategy to transform rusty iron products into Prussian blue as high-performance cathode materials and recover the rusty iron products to their original status. Owing to the high crystalline and Na + content, the rusty iron derived Prussian blue shows a high specific capacity of 145 mAh g − 1 and excellent cycling stability over 3500 cycles. Through the in situ X-ray diffraction and in situ Raman spectra, it is found that the impressive ion storage capability and stability are greatly related to the suppressed structure distortion during the charge/discharge process. The ions migration mechanism and possibility as universal host of other kinds of ions are further illuminated by density functional theory calculations. This work provides a new strategy for recycling wasted materials into high value-added materials for sustainable battery systems, and is adaptable in the nanomedicine, catalysis, sensors, and gas storage applications.
Publisher: Elsevier BV
Date: 12-2020
Publisher: AIP Publishing
Date: 09-10-2017
DOI: 10.1063/1.4989667
Abstract: An interface is constructed based on a bismuth ferrite oxide (BFO) thin film and p-type silicon, and the temperature dependence of the interface properties has been studied systematically using terahertz time-domain spectroscopy. The BFO/Si interface exhibits quasi-two-dimension electron gas (2DEG) transport in the temperature range of 80 to 140 K: the electrons at the interface possess large electron mobility (∼106 cm2/V s) and long scattering time (∼100 ps). As the temperature is higher than 140 K, an abrupt decrease in THz interface conductivity is observed due to the breakdown of the 2DEG induced by the surface phase transition in the BFO thin film. Our result reveals that the interface formed between BFO and Si provides a special platform for designing and fabricating THz photonic devices.
Publisher: AIP Publishing
Date: 11-08-2020
DOI: 10.1063/5.0011931
Abstract: A magnetic field sensor is designed and fabricated using a piezoelectric face shear mode Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT)/Metglas magneto-electric (ME) composite. An outstanding ME coupling coefficient up to 1600 V/(cm Oe) was experimentally achieved, being ∼50% higher than the value from the extensional PMN–PT/Metglas ME composite with the same volume. The detection limit was found to be 2 × 10−6 Oe for the DC magnetic field, while it was 2 × 10−8 Oe for the AC magnetic field. The sensitivity of the face shear mode PMN–PT/Metglas ME composite is about one order of magnitude higher than that of a 32 extensional mode PMN–PT/Metglas based ME composite in sensing a weak DC magnetic field. A sensing array was also designed based on the ME composite to image weak DC magnetic fields, demonstrating a great potential promising for sensing weak magnetic fields.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0CP06354A
Abstract: Magnetization reversal occurs over 1 min for NdFeO 3 crystals, while it occurs over a fraction of a second for ErFeO 3 crystals.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0NR03704D
Abstract: Our work not only reports the discovery of a novel TNL material, but also builds the link between the TNL and thermoelectric properties.
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D2QI02515A
Abstract: Coupling oxygen vacancy gradient distribution and flexoelectricity for the enhancement of ferroelectric photovoltaic effects.
Publisher: Elsevier BV
Date: 04-2023
Publisher: MDPI AG
Date: 31-03-2022
DOI: 10.3390/NANO12071159
Abstract: A magnonic metamaterial in the presence of spatially modulated Dzyaloshinskii-Moriya interaction is theoretically proposed and demonstrated by micromagnetic simulations. By analogy to the fields of photonics, we first establish magnonic Snell's law for spin waves passing through an interface between two media with different dispersion relations due to different Dzyaloshinskii-Moriya interactions. Based on magnonic Snell's law, we find that spin waves can experience total internal reflection. The critical angle of total internal reflection is strongly dependent on the sign and strength of Dzyaloshinskii-Moriya interaction. Furthermore, spin-wave beam fiber and spin-wave lens are designed by utilizing the artificial magnonic metamaterials with inhomogeneous Dzyaloshinskii-Moriya interactions. Our findings open up a rich field of spin waves manipulation for prospective applications in magnonics.
Publisher: MDPI AG
Date: 14-09-2017
DOI: 10.3390/MA10091078
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0SE01633K
Abstract: Understanding of the operating mechanism of a ‘breathable’ water-splitting electrode, which extracts evolved gas without forming bubbles, is advanced.
Publisher: Springer Science and Business Media LLC
Date: 16-09-2022
Publisher: Springer Science and Business Media LLC
Date: 08-11-2018
DOI: 10.1038/S41598-018-34881-Y
Abstract: Directly coupled hard and soft ferromagnets were popularly used as the hybridized electrodes to enhance tunnel magnetoresistance (TMR) ratio in the perpendicular magnetic tunnel junction (pMTJ). In this paper, we employ the density functional theory (DFT) with general gradient approximation (GGA) to investigate the interfacial structure and magnetic behavior of tetragonal Heusler-type MnGa (MG)/L2 1 -Co 2 MnSi (CMS) Heusler alloy bilayers with the MnGa being D0 22 -MnGa alloy (Mn 3 Ga) and L1 0 -MnGa alloy (MnGa). The MM-MS_B interface with the bridge (B) connection of MnMn termination (MM) of D0 22 - and L1 0 -MnGa layers to MnSi termination (MS) of CMS layers is found to be most stable in the energy point of view. Also, a strong antiferromagnetic coupling and relatively higher spin polarization can be observed in the MM-MS_B interface. Further, a remarkable potential difference to derive electrons to transfer from MG layer to CMS layer appears at the interface. These theoretical results indicate that the MG/CMS bilayers are promising candidates as coupled composites, and moreover, the D0 22 -MG/CMS bilayer is better than L1 0 -MG/CMS bilayer due to its larger spin polarization and built-in field at the interface.
Publisher: Elsevier BV
Date: 10-2022
Publisher: American Physical Society (APS)
Date: 15-06-2021
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1TA10692A
Abstract: Multi-layered nanostructures obtained by Cu 2 Se achieve extremely low thermal conductivity in AgCuTe.
Publisher: Elsevier BV
Date: 06-2022
Publisher: Elsevier BV
Date: 05-2022
Publisher: AIP Publishing
Date: 06-02-2018
DOI: 10.1063/1.5010101
Abstract: A method to synthesize molybdenum carbides has been developed based on microwave plasma treatment with methane and hydrogen mixed gases, using a microwave-plasma chemical vapor deposition device. The device framework and its mechanism are described in detail. Two-dimensional α-Mo2C has been directly synthesized by a plate-to-plate substrate holder structure with a microwave power of 920 W and a partial pressure of 20 kPa. In-situ optical emission spectroscopy was used to measure the radical types in the plasma ball during glow discharge. The as-grown α-Mo2C s les were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy to determine their phases, purity and chemical groups. The superconducting transition temperature was measured, and the transition temperatures of the relevant phases are discussed in detail. The results confirmed that this method is an efficient way to obtain molybdenum carbides and inspire new research interest in transition metal carbides, which have many intrinsic local properties and applications.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0TC01220C
Abstract: Review article of the solid-state crystal growth (SSCG) technique and the progress of lead-free ferroelectric single crystals for piezoelectric applications.
Publisher: AIP Publishing
Date: 24-01-2020
DOI: 10.1063/1.5131411
Abstract: BiFeO3, a typical multiferroic compound, owns complicated interactions among its charge, lattice, and spin degrees, while largely remaining a mystery. In this work, the BiFeO3 single crystal has been investigated in pulsed high magnetic fields up to 50 T. The lattice, spin, and charge orderings are found to couple with each other strongly. High magnetic field could drive the spin cycloid phase to a canted antiferromagnetic phase while accompanied by a clear magnetostriction response and weakening of ferroelectric polarization. The critical magnetic field for the magnetic phase transition was shifted to the lower magnetic field region by an external electric field over a broad temperature range, which indicates the complex interaction among magnetization, electrical polarization, and crystal lattice. This work has provided a clear picture to show the synergetic response of multiple ordering parameters during the magnetic phase transition in BiFeO3, which could benefit the design of BiFeO3 based spintronic devices and novel multiferroic materials with strong magnetoelectric coupling.
Publisher: Wiley
Date: 15-11-2019
Abstract: Bismuth ferrite (BiFeO
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D2CP03477H
Abstract: AgCuTe alloying introduces endotaxial nanostructures in SnTe, which significantly decrease thermal conductivity and enhance ZT .
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1NJ06127E
Abstract: Recently, piezo-catalysts have gained considerable attention owing to their unique ability to degrade pollutants by harvesting trivial mechanical energy from the surrounding environment.
Publisher: Wiley
Date: 16-08-2021
Abstract: As a promising candidate for the much‐desired low power consumption spintronic devices, 2D magnetic van der Waals material also provides a versatile platform for the design and control of topological spin textures. In this work on WTe 2 /CrCl 3 bilayer van der Waals heterostructures, a complete Néel‐type skyrmion–bimeron–ferromagnet phase transition is demonstrated, accompanied by the evolution of the topological number. This cyclic transition, mediated by a perpendicular magnetic field, is largely driven by the competition between the out‐of‐plane magnetocrystalline anisotropy and magnetic dipole–dipole interaction. In the presence of a driving current, the Néel‐type skyrmion gains a higher velocity yet larger skyrmion Hall angle, in comparison to the bimeron. By incorporating a ferroelectric CuInP 2 S 6 monolayer as a substrate, writing and erasing of skyrmions may be regulated using a ferroelectric polarization. This work sheds light on a novel approach to the design and control of magnetic skyrmions on 2D van der Waals materials.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1CE00679G
Abstract: We reported three hybrid organic–inorganic perovskite single crystals of (CH 3 NH 3 ) 2 MnCl 4 , (CH 3 NH 3 ) 2 CuCl 4 and (CH 3 NH 3 ) 2 CoCl 4 . Magnetic measurements show that all the single crystals display magnetic ordering at low temperature.
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1TC05482A
Abstract: Li 1.04 (Cd 1− x Mn x )As DMSs were synthesized by a high temperature solid state reaction method. A Curie temperature of 318 K has been achieved for x = 0.08. The hysteresis loops at different temperatures demonstrate room temperature ferromagnetism.
Publisher: AIP Publishing
Date: 06-2018
DOI: 10.1063/1.5018872
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D2CP05753K
Abstract: The effect of temperature change on the magnetic moment for rare earth ions in RFeO 3 .
Publisher: Elsevier BV
Date: 09-2020
Publisher: AIP Publishing
Date: 13-02-2023
DOI: 10.1063/5.0136219
Abstract: Here, we report the growth of (Sr, Ca) Nd2Fe2O7 single crystals with the Ruddlesden–Popper structure using an optical floating-zone method. A significantly anisotropic magneto-dielectric effect (MD), ab-plane and c-axial MD coefficients reaching −12.3% and −8.4% measured at 103 Hz in a 1 T magnetic field, can be obtained in a SrNd2Fe2O7 crystal at room temperature. The corresponding anisotropic MD ratio can be reached as high as 1.46. With an increase in the Ca concentration, the MD effect decreases dramatically and is eventually completely suppressed in both directions. Analysis of magnetic properties and 57Fe Mössbauer spectra suggests that the anisotropic MD effects in SrNd2Fe2O7 can be attributed to polaronic hopping between two neighboring Fe3+ ions through oxygen vacancies in an anisotropically antiferromagnetic matrix the disappearance of the MD effect in Ca-doped SrNd2Fe2O7 is a consequence of the suppression of the antiferromagnetism. Our work suggests that the significantly anisotropic MD effect in SrNd2Fe2O7 crystals at room temperature can be used in magneto-dielectric controlled devices.
Publisher: AIP Publishing
Date: 20-08-2018
DOI: 10.1063/1.5042265
Abstract: Hybrid materials provide an efficient alternative route on improving the thermoelectric performance compared with doping elements. Especially, the insertion of carbon nanotubes plays an effective role in modulating the electrical transport properties and phonon scattering simultaneously. We fabricated a multi-walled carbon nanotube (MWCNTs) doped α-MgAgSb-based hybrid material and researched its thermoelectric properties in detail. The introduced MWCNTs enhanced carrier transport due to the metallic character of MWCNTs and phonon dispersion by the additional interfaces of insertions. The results showed that the electrical conductivity in α-MgAgSb/CNTs was remarkably enhanced especially at MgAg0.97Sb0.99/0.15 wt. % CNTs boosting to 1.6 times than that of CNTs-free MgAg0.97Sb0.99. In addition, the thermal conductivity(κ0.1) of MgAg0.97Sb0.99/0.1 wt. % CNTs was reduced to 0.85 κ0. As a result, the ZT value at room temperature was efficiently improved from 0.55 to 0.83, 1.5 times higher, and a high ZT value of 1.05 at 375 K was obtained. In addition, the dimensionless material factor B* increased from 0.98 to 1.49 at the doping level of 0.1 wt. % CNTs at 300 K, which revealed that MWCNTs significantly enhanced the thermoelectric performance of α-MgAgSb.
Publisher: American Chemical Society (ACS)
Date: 19-01-2022
DOI: 10.1021/ACS.JPCLETT.1C03903
Abstract: The couplings among fundamental quantum parameters provide versatile freedom of manipulations for useful electronic structures, based on which optimized oxygen evolution reaction (OER) performances can be achieved. In this work, we demonstrate the successful regulation of the electronic structure in layered Na
Publisher: Wiley
Date: 28-11-2023
Abstract: Water splitting is the most important process for making green hydrogen. The positive effects of ferroelectric polarization in various kinds of water splitting are well recognized, but the study of electrocatalytic water splitting is still in its infancy. Herein, a family of intrinsic ferroelectrics with a flexible tetragonal tungsten bronze structure is chosen to accommodate oxygen evolution reaction (OER) active sites together with its freedom for tuning the ferroelectric polarization. It is found that the OER performance is positively correlated with the ferroelectric polarization, with a significant reduction in the overpotential of ≈40 mV at 10 mA cm −2 , coming from two trade‐off effects, i.e., enhancement of the surface adsorption and band tilting for fast electron transfer. This study not only fills the gap between electrocatalytic water splitting and the band structure but also proposes ferroelectric polarization as a powerful tool to enhance water splitting for clean hydrogen in several ways.
Publisher: AIP Publishing
Date: 09-07-2018
DOI: 10.1063/1.5037119
Abstract: We use terahertz (THz) magnetic and electric fields to investigate the magnetic and optoelectronic responses of the Sm0.5Pr0.5FeO3 (SPFO) crystal, respectively, by THz time-domain spectroscopy. It is found that the spin reorientation transition (SRT) in SPFO occurs in the temperature range of 175–210 K. The SRT is not observed in PrFeO3. The quasi-antiferromagnetic magnon frequency has a blue-shift from 0.42 THz (PrFeO3) to 0.46 THz (SPFO) at room temperature, due to the enhanced anisotropy constant. The refractive index of SPFO in the THz frequency decreases around 3% compared with that of the PrFeO3 crystal. In addition, it can be found that the energy scale of crystal-field transitions has a red-shift for the doped single crystal. We expect our results to make rare-earth orthoferrites accessible to potential applications in THz spintronic devices.
Publisher: Elsevier BV
Date: 03-2022
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0TA04612D
Abstract: Eco-friendly energy harvesters with high output for effectively harvesting mechanical energy over a broad temperature range.
Publisher: Springer Science and Business Media LLC
Date: 06-08-2021
DOI: 10.1038/S41467-021-25068-7
Abstract: Artificial photosynthesis, light-driving CO 2 conversion into hydrocarbon fuels, is a promising strategy to synchronously overcome global warming and energy-supply issues. The quaternary AgInP 2 S 6 atomic layer with the thickness of ~ 0.70 nm were successfully synthesized through facile ultrasonic exfoliation of the corresponding bulk crystal. The sulfur defect engineering on this atomic layer through a H 2 O 2 etching treatment can excitingly change the CO 2 photoreduction reaction pathway to steer dominant generation of ethene with the yield-based selectivity reaching ~73% and the electron-based selectivity as high as ~89%. Both DFT calculation and in-situ FTIR spectra demonstrate that as the introduction of S vacancies in AgInP 2 S 6 causes the charge accumulation on the Ag atoms near the S vacancies, the exposed Ag sites can thus effectively capture the forming *CO molecules. It makes the catalyst surface enrich with key reaction intermediates to lower the C-C binding coupling barrier, which facilitates the production of ethene.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0RA10807C
Abstract: Searching for a new approach in environmental remediation in terms of dye degradation is important in industrialized society.
Publisher: American Chemical Society (ACS)
Date: 03-10-2023
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0CP02334E
Abstract: α-FeSi 2 is a valuable candidate for spintronics application by utilization of type I, type II, and hybrid-type topological nodal line semimetals in a single material tuned by mechanical strain.
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D2TC01889F
Abstract: The crystal structure of bulk Fe 3 GeTe 2 (a) the side views of (b) the 0° and (c) the 180° twist-stacked Fe 3 GeTe 2 bilayers, as well as the top views of (d) the 0° and (e) the 180° twist-stacked bilayers.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0NR01949F
Abstract: Polycrystalline SnSe s le with graphene embedded in realized the enhancement of phonon scattering and achieved ultralow thermal conductivity.
Publisher: AIP Publishing
Date: 12-2018
DOI: 10.1063/1.5042604
Publisher: American Physical Society (APS)
Date: 23-10-2023
Publisher: Springer Science and Business Media LLC
Date: 08-2017
Publisher: American Chemical Society (ACS)
Date: 12-09-2023
Publisher: AIP Publishing
Date: 20-03-2020
DOI: 10.1063/1.5115518
Abstract: Rare earth orthoferrites demonstrate great application potentials in spintronics and optical devices due to their multiferroic and magnetooptical properties. In RFeO3, magnetic R3+ undergo a spontaneous spin reorientation in a temperature range determined by R (rare earth), where the magnetic structure changes from Γ2 to Γ4. The b-axis component of their magnetic moment, Mb, is reported in numerous neutron diffraction studies to remain zero at all temperatures. More sensitive magnetometer measurements reveal a small non-zero Mb, which is minute above ∼200 K. Mb increases with cooling and reaches values of ∼10–3 μB/f.u. at temperatures within or below the spin reorientation temperatures. Our results can be explained by assuming the Fe3+ spins as the origin of non-zero Mb, while R3+ spins suppress Mb. The representation analysis of point groups shows that non-zero Mb is associated with a small admixture of the Γ3 phase to Γ2 or Γ4. Such a mixing of the three magnetic phases requires at least a fourth order of the spin Hamiltonian for RFeO3 to describe the non-zero Mb.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1TB01036K
Abstract: In this work, size- and shape-controlled two-dimensional (2D) superparamagnetic maghemite (γ-Fe2O3) quantum flakes (MQFs) with high surface area and mesoporosity were prepared by facile hydrothermal synthesis for biological applications. These quantum flakes exhibited superparamagnetic behaviours over a wide temperature range of 75-950 K with high saturation magnetization of Ms - 23 emu g-1 and a lower coercivity of Hc - 6.1 Oe. MQFs also demonstrated a good colloidal stability and a positively charged flake surface. Selective toxicity dependent upon selective ROS scavenging/generation and cellular MQF uptake towards non-malignant human keratinocyte (HaCaT) and malignant melanoma (A357) and human breast cancer (MDA-MB 231) cell lines were witnessed. An increased ROS concentration resulted due to the peroxidase-like activity of MQFs in malignant cells. In contrast, ROS scavenging was observed in non-malignant cells due to dominant catalase-like activity. In vitro fluorescence properties added the diagnostic ability to the ambit of MQFs. Furthermore, the therapeutic efficiency could be significantly enhanced by the hyperthermic (25-47 °C) ability of MQF in cancerous cells. Our findings reveal the novel theranostic MQF structure with immense cancer therapeutic potential via augmentation of ROS generation by hyperthermia in a selective microenvironment.
Publisher: Elsevier BV
Date: 06-2023
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1NR01093J
Abstract: The weak interlayer exchange coupling introduced by CrOBr bilayer makes it easier to be regulated by ferroelectric polarization in CrOBr-bilayer/In 2 Se 3 heterostructure.
Publisher: American Physical Society (APS)
Date: 29-07-2021
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1NR00139F
Abstract: 2D A 3 C 2 (A = Ti, Zr, and Hf) materials are reported as new ferromagnetic materials with intrinsic magnetism and good stability.
Publisher: AIP Publishing
Date: 14-04-2021
DOI: 10.1063/5.0035622
Abstract: Magnetic skyrmions are considered a promising candidate for the next-generation information processing technology. Being topologically robust, magnetic skyrmions are swirling spin textures that can be used in a broad range of applications from memory devices and logic circuits to neuromorphic computing. In a magnetic medium lacking inversion symmetry, magnetic skyrmion arises as a result of the interplay among magnetic exchange interaction, Dzyaloshinskii-Moriya interaction, and magnetic anisotropy. Instrumental to the integrated skyrmion-based applications are the creation and manipulation of magnetic skyrmions at a designated location, absent any need of a magnetic field. In this paper, we propose a generic design strategy to achieve that goal and a model system to demonstrate its feasibility. By implementing a disk-shaped thin film heterostructure with an inhomogeneous perpendicular magnetic anisotropy, stable sub-100-nm size skyrmions can be generated without magnetic field. This structure can be etched out via, for ex le, focused ion beam microscope. Using micromagnetic simulation, we show that such heterostructure not only stabilizes the edge spins of the skyrmion but also protects its rotation symmetry. Furthermore, we may switch the spin texture between skyrmionic and vortex-like ones by tuning the slope of perpendicular anisotropy using a bias voltage. When embedded into a magnetic conductor and under a spin polarized current, such heterostructure emits skyrmions continuously and may function as a skyrmion source. This unique phenomenon is dubbed a skyrmion battery effect. Our proposal may open a novel venue for the realization of all-electric skyrmion-based devices.
Publisher: Springer Science and Business Media LLC
Date: 23-03-2022
DOI: 10.1038/S41467-022-28963-9
Abstract: Transition metal dissolution in cathode active material for Li-based batteries is a critical aspect that limits the cycle life of these devices. Although several approaches have been proposed to tackle this issue, this detrimental process is not yet overcome. Here, benefitting from the knowledge developed in the semiconductor research field, we apply an epitaxial method to construct an atomic wetting layer of LaTMO 3 (TM = Ni, Mn) on a LiNi 0.5 Mn 1.5 O 4 cathode material. Experimental measurements and theoretical analyses confirm a Stranski–Krastanov growth, where the strained wetting layer forms under thermodynamic equilibrium, and it is self-limited to monoatomic thickness due to the competition between the surface energy and the elastic energy. Being atomically thin and crystallographically connected to the spinel host lattices, the LaTMO 3 wetting layer offers long-term suppression of the transition metal dissolution from the cathode without impacting its dynamics. As a result, the epitaxially-engineered cathode material enables improved cycling stability (a capacity retention of about 77% after 1000 cycles at 290 mA g −1 ) when tested in combination with a graphitic carbon anode and a LiPF 6 -based non-aqueous electrolyte solution.
Publisher: AIP Publishing
Date: 09-2023
DOI: 10.1063/5.0159948
Publisher: Springer Science and Business Media LLC
Date: 09-02-2021
DOI: 10.1038/S41467-021-21202-7
Abstract: (K,Na)NbO 3 based ceramics are considered to be one of the most promising lead-free ferroelectrics replacing Pb(Zr,Ti)O 3 . Despite extensive studies over the last two decades, the mechanism for the enhanced piezoelectricity in multi-elements doped (K,Na)NbO 3 ceramics has not been fully understood. Here, we combine temperature-dependent synchrotron x-ray diffraction and property measurements, atomic-scale scanning transmission electron microscopy, and first-principle and phase-field calculations to establish the dopant–structure–property relationship for multi-elements doped (K,Na)NbO 3 ceramics. Our results indicate that the dopants induced tetragonal phase and the accompanying high-density nanoscale heterostructures with low-angle polar vectors are responsible for the high dielectric and piezoelectric properties. This work explains the mechanism of the high piezoelectricity recently achieved in (K,Na)NbO 3 ceramics and provides guidance for the design of high-performance ferroelectric ceramics, which is expected to benefit numerous functional materials.
Publisher: Springer Science and Business Media LLC
Date: 22-07-2022
DOI: 10.1038/S41524-022-00833-4
Abstract: Two-dimensional (2D) van der Waals (vdW) materials provide the versatile playground to stack two or more vdW layers for creation of superior materials with desired properties. Here we theoretically adopt a twisted stack-engineering of two LaBr 2 monolayers to break space inversion symmetry for ferroelectricity and ultimately multiferroism. The enhancement and reversal of electric polarization are accompanied with the transition from interlayer ferromagnetic and antiferromagnetic orderings, demonstrating an effective magnetoelectric coupling effect with a mechanism dissimilar to that of the conventional multiferroics. Magnetization dynamics simulations show that such magnetic phase transition can excite topologically protected bimeron, and the skyrmion Hall effect can be suppressed by bilayer-bimeron stabilized in both ferromagnetic and antiferromagnetic configurations. Moreover, in the small-angle twisted moiré superlattice, the uniform polarization will evolve into a staggered domain structure, accompanied with the appearance of bimeron, which forms a significant discrepancy with the non-twisted stack-engineered multiferroic LaBr 2 bilayer. This work provides a strategy for 2D multiferroic materials by twisted stack engineering of magnetic single layers.
Publisher: Research Square Platform LLC
Date: 24-02-2021
DOI: 10.21203/RS.3.RS-225023/V1
Abstract: The quaternary AgInP2S6 atomic layer with the thickness of ~ 0.70 nm were successfully synthesized through facile ultrasonic exfoliation of the corresponding bulk crystal. The ultrathin sheet exhibits efficiently photocatalytic conversion of CO2 into CO as a major product and minority of CH4 and C2H4 in the presence of water vapor. The sulfur defect engineering on this atomic layer through a H2O2 etch process can excitingly enable to change the CO2 photoreduction reaction pathway to steer dominant generation of ethene (C2H4) important chemical with the yield-based selectivity reaching ~73% and the electron-based selectivity as high as ~89%, and the quantum yield of 0.51% at wavelength of 415 nm. Both DFT calculation and in-situ FTIR demonstrate as the introduction of S vacancies in AgInP2S6 causes the charge accumulation on the Ag atoms near the S vacancies, the exposed Ag sites can thus effectively capture the forming *CO molecules, making the catalyst surface enrich with key reaction intermediates to lower the C-C binding coupling barrier, which facilitates the production of C2H4. Surface photovoltage measurement confirms that atomically ultrathin structure of the exfoliated AgInP2S6 can shorten the transfer distance of charge carriers from the interior onto the surface, thus decrease the recombination in body and improve the catalytic efficiency. This work may provide fresh insights into the design of atomically thin photocatalyst framework for CO2 reduction and establish an ideal platform for reaffirming the versatility of defect engineering in tuning catalytic activity and selectivity.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1NR04816C
Abstract: An Ni(NCS) 2 monolayer is a robust bipolar magnetic semiconductor, in which completely spin-polarized currents with reversible spin polarization can be created and controlled simply by applying a gate voltage.
Publisher: Elsevier BV
Date: 02-2021
Publisher: American Physical Society (APS)
Date: 07-07-2023
Location: Australia
No related grants have been discovered for Zhenxiang Cheng.