- 2D Materials and Applications
- Graphene research and applications
- Topological Materials and Phenomena
- Quantum and electron transport phenomena
- MXene and MAX Phase Materials
- Semiconductor materials and devices
- Physics of Superconductivity and Magnetism
- Perovskite Materials and Applications
- Plasmonic and Surface Plasmon Research
- Advanced Thermoelectric Materials and Devices
- Photonic and Optical Devices
- Metamaterials and Metasurfaces Applications
- Molecular Junctions and Nanostructures
- Thermal Radiation and Cooling Technologies
- Advancements in Semiconductor Devices and Circuit Design
- Electronic and Structural Properties of Oxides
- Semiconductor materials and interfaces
- Mechanical and Optical Resonators
- ZnO doping and properties
- Magnetic properties of thin films
- Advanced Photocatalysis Techniques
- Nanowire Synthesis and Applications
- Advanced Condensed Matter Physics
- Ga2O3 and related materials
- Semiconductor Quantum Structures and Devices
Singapore University of Technology and Design
2016-2025
Xi’an University of Posts and Telecommunications
2022
DexMat (United States)
2021
Wright-Patterson Air Force Base
2021
University of Illinois Urbana-Champaign
2021
University of Cambridge
2021
University of Cincinnati
2021
Massachusetts Institute of Technology
2019
National University of Singapore
2018
Engineering Associates (United States)
2018
Abstract Photocatalytic water-splitting for hydrogen generation by sunlight provides a new route to address energy and environmental problems. In recent years, tremendous efforts have been devoted designing highly efficient photocatalysts (PCs). Adequate light absorption, effective photogenerated carrier separation, sufficiently large overpotentials water redox are crucial in achieving high solar-to-hydrogen (STH) efficiency. These parameters thus strongly influence the design of novel...
MXene, a new class of two-dimensional nanomaterials, have drawn increasing attention as emerging materials for sensing applications. However, MXene-based surface plasmon resonance sensors remain largely unexplored. In this work, we theoretically show that the sensitivity sensor can be significantly enhanced by combining Ti 3 C 2 T x MXene and transition metal dichalcogenides. A high 198 ∘ /RIU (refractive index unit) with enhancement 41.43% was achieved in aqueous solutions ∼1.33) employment...
This Perspective reviews the fundamental physics of space–charge interactions that are important in various media: vacuum gap, air liquids, and solids including quantum materials. It outlines critical recent developments since a previous review paper on diode [Zhang et al. Appl. Phys. Rev. 4, 011304 (2017)] with particular emphasis theoretical aspects limited current (SCLC) model: at nano-scale, time-dependent, transient behaviors; higher-dimensional models; transitions between electron...
Abstract Metal contacts to two-dimensional (2D) semiconductors are often plagued by the strong Fermi level pinning (FLP) effect which reduces tunability of Schottky barrier height (SBH) and degrades performance 2D semiconductor devices. Here, we show that MoSi 2 N 4 WSi monolayers—an emerging family with exceptional physical properties—exhibit strongly suppressed FLP wide-range tunable SBH. An exceptionally large SBH slope parameter S ≈ 0.7 is obtained outperforms vast majority other...
Zinc metal is an ideal candidate for aqueous rechargeable batteries due to its high theoretical capacity and natural abundance. However, commercialization inevitably challenged by several critical factors such as dendrite growth parasitic side-reactions, leading low coulombic efficiency a limited lifespan. Herein, modified Zn foil with zincophilic ZnSe layer deposited simple selenization process proposed. An order of magnitude stronger adsorption capability toward Zn2+ ions uniform ion...
In this work, we perform a first-principle study to investigate the atomic and electronic structures of ${\mathrm{C}}_{3}{\mathrm{N}}_{4}/{\mathrm{MoSi}}_{2}{\mathrm{N}}_{4}$ van der Waals heterostructure (vdWH) as well its tunable structure via interlayer coupling an external perpendicular electric field. The vdWH is structurally thermodynamically stable at room temperature. Our results demonstrate that exhibits semiconducting characteristic with direct band gap 1.86/2.66 eV given by...
The atomic, electronic, optical, and mechanical properties of penta-like two-dimensional PdPX (X = O, S, Te) nanosheets have been systematically investigated using density functional theory calculations. All three exhibit dynamic stability on the basis an analysis phonon dispersions Born criteria, respectively. monolayers are found to be brittle structures. Our calculations demonstrate that semiconducting characteristics with indirect band gaps 0.93 (1.99), 1.34 (2.11), 0.74 (1.51) eV for X...
Recent experimental synthesis of ambient-stable MoSi2N4 monolayer has garnered enormous research interest. The intercalation morphology MoSi2N4—composed a transition metal nitride (Mo-N) inner sub-monolayer sandwiched by two silicon (Si-N) outer sub-monolayers—has motivated the computational discovery an expansive family synthetic MA2Z4 monolayers with no bulk (3D) material counterpart (where M = metals or alkaline earth metals; A Si, Ge; and N N, P, As). exhibit interesting electronic,...
The photocatalytic overall water splitting can be achieved in the As/In 2 Se 3 vdW heterostructure by regulating polarization direction of In layer.
We identify a new universality in the carrier transport of two-dimensional (2D) material-based Schottky heterostructures. show that reversed saturation current (J) scales universally with temperature (T) as log(J/T^{β})∝-1/T, β=3/2 for lateral heterostructures and β=1 vertical heterostructures, over wide range 2D systems including nonrelativistic electron gas, Rashba spintronic systems, single- few-layer graphene, transition metal dichalcogenides, thin films topological solids. Such...
Despite much anticipation of valleytronics as a candidate to replace the ageing CMOS-based information processing, its progress is severely hindered by lack practical ways manipulate valley polarization all-electrically in an electrostatic setting. Here we propose class all-electric-controlled filter, valve and logic gate based on valley-contrasting transport merging Dirac cones system. The central mechanism these devices lies pseudospin-assisted quantum tunneling which effectively quenches...
Abstract Knots are intricate structures that cannot be unambiguously distinguished with any single topological invariant. Momentum space knots, in particular, have been elusive due to their requisite finely tuned long-ranged hoppings. Even if constructed, probing linkages and "drumhead” surface states will challenging the high precision needed. In this work, we overcome these practical technical challenges RLC circuits, transcending existing theoretical constructions which necessarily break...
Abstract Electrically contacting two‐dimensional (2D) materials is an inevitable process in the fabrication of devices for both study fundamental nanoscale charge transport physics and design high‐performance novel electronic optoelectronic devices. The electrical contact formation interfacial injection critically underlies performance, energy‐efficiency functionality 2D‐material‐based devices, thus representing one key factors determining whether 2D can be successfully implemented as a new...
With exceptional electrical and mechanical properties at the same time air-stability, layered MoSi2N4 has recently draw great attention. However, band structure engineering via strain electric field, which is vital for practical applications, not yet been explored. In this work, we show that biaxial external field are effective ways gap of bilayer MoSi$_2$N$_4$ WSi$_2$N$_4$. It found can lead to indirect direct transition. On other hand, result in semiconductor metal Our study provides...
Janus transition metal dichalcogenides with a built-in structural cross-plane asymmetry have recently emerged as new class of two-dimensional materials large dipole. By using the density functional theory calculation, we report formation different Schottky barriers for PtSSe and graphene based van der Waals heterostructures, where barrier height (SBH) type contact can be controlled by adjusting interlayer distance, applying an external electric field, having multiple layers PtSSe. It is...
Low-symmetry penta-PdPSe (Pd4P4Se4) with intrinsic in-plane anisotropy was synthesized successfully [P. Li et al., Adv. Mater., 2021, 2102541]. Motivated by this experimental discovery, we investigate the structural, mechanical, electronic, optical and thermoelectric properties of PdPSe nanosheets via density functional theory calculations. The phonon dispersion, molecular dynamics simulation, cohesive energy mechanical are verified to confirm its stability. spectrum represents a striking...
A van der Waals (VDW) heterostructure offers an effective strategy to create designer physical properties in vertically stacked two-dimensional (2D) materials, and a new paradigm designing novel 2D devices. In this work, we investigate the structural electronic features of BP/MoGe2N4 heterostructure. We show that exists multiple structurally stable stacking configuration, thus revealing experimental feasibility fabricating such heterostructures. Electronically, is direct band gap...
Strain is an effective method to tune the electronic properties of two-dimension (2D) materials, and can induce novel phase transition. Recently, 2D $\mathrm{MA_2Z_4}$ family materials are interest because their emerging topological, magnetic superconducting properties. Here, we investigate impact strain effects ($a/a_0$:0.96$\sim$1.04) on physical Janus monolayer $\mathrm{VSiGeN_4}$ as a derivative $\mathrm{VSi_2N_4}$ or $\mathrm{VGe_2N_4}$, which possesses dynamical, mechanical thermal...
Following the successful synthesis of single-layer metallic Janus MoSH and semiconducting MoSi2N4, we investigate electronic interfacial features metal/semiconductor MoSH/MoSi2N4 van der Waals (vdW) contact. We find that contact forms p-type Schottky (p-ShC type) with small barrier (SB), suggesting can be considered as an efficient to MoSi2N4 semiconductor high charge injection efficiency. The structure vdW heterostructure are tunable under strain electric fields, which give rise SB change...
Multiferroic van der Waals (vdW) heterostrucutres offers an exciting route towards novel nanoelectronics and spintronics device technology. Here we investigate the electronic transport properties of multiferroic vdW heterostructure composed ferromagnetic FeCl$_2$ monolayer ferroelectric Sc$_2$CO$_2$ using first-principles density functional theory quantum simulations. We show that FeCl$_2$/Sc$_2$CO$_2$ can be reversibly switched from semiconducting to half-metallic behavior by electrically...
Van de Waals heterostructures (VDWH) is an emerging strategy to engineer the electronic properties of two-dimensional (2D) material systems. Motivated by recent discovery MoSi$_2$N$_4$ - a synthetic septuple-layered 2D semiconductor with exceptional mechanical and properties, we investigate synergy \ce{MoSi2N4} wide band gap (WBG) monolayers GaN ZnO using first-principle calculations. We find that MoSi$_2$N$_4$/GaN direct Type-I VDWH while MoSi$_2$N$_4$/ZnO indirect Type-II VDWH....
Abstract 2D materials van der Waals heterostructures (vdWHs) provide a revolutionary route toward high‐performance solar energy conversion devices beyond the conventional silicon‐based pn junction cells. Despite tremendous research progress accomplished in recent years, searches of vdWHs with exceptional excitonic cell efficiency and optical properties remain an open theoretical experimental quest. Here, this study shows that vdWH family composed MoSi 2 N 4 WSi monolayers provides compelling...
Coupling charge impurity scattering effects and charge-carrier modulation by doping can offer intriguing opportunities for atomic-level control of resistive switching (RS). Nonetheless, such have remained unexplored memristive applications based on 2D materials. Here a facile approach is reported to transform an RS-inactive rhenium disulfide (ReS2 ) into effective material through interfacial induced molybdenum-irradiation (Mo-i) doping. Using ReS2 as model system, this study unveils unique...
Altermagnetism can achieve spin-split bands in collinear symmetry-compensated antiferromagnets. Here, we predict altermagnetic order Janus monolayer Cr2SO with eliminated inversion symmetry, which realize the combination of piezoelectricity and altermagnetism a two-dimensional (2D) material, namely, 2D piezoelectric altermagnetism. It is found that an semiconductor, both valence conduction are near Fermi level. The has large out-of-plane (|d31| = 0.97 pm/V), highly desirable for ultrathin...
Two-dimensional (2D) niobium oxydihalide NbOI2 has been recently demonstrated as an excellent in-plane piezoelectric and nonlinear optical material. Here we show that Janus oxydihalide, NbOXY (X, Y = Cl, Br, I X ≠ Y), is a multifunctional anisotropic semiconductor family with exceptional piezoelectric, electronic, photocatalytic properties. are stable flexible monolayers band gap around the visible light regime of ∼1.9 eV. The carrier mobility exhibits exceptionally strong anisotoropy ratio...