Article
Chemistry, Physical
Cheng-Wei Wu, Fan Li, Yu-Jia Zeng, Hongwei Zhao, Guofeng Xie, Wu-Xing Zhou, Qingquan Liu, Gang Zhang
Summary: By combining first-principles calculations, machine learning fitted potential, and solving the phonon Boltzmann transport equation, we propose a new group of two-dimensional covalent organic frame semiconductors 2AL-PR-X (X = 2H, Ni, Pt, Zn) as promising organic thermoelectric materials. We found that embedding metal atoms in the center can greatly enhance the stability of the porphyrin ring and reduce thermal conductivity. Among the studied 2AL-PR-X materials, 2AL-PR-Pt shows the best thermoelectric performance with a peak ZT of 0.32 at room temperature and around 0.9 at 800 K.
APPLIED SURFACE SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Yan Yin, Min Yi, Wanlin Guo
Summary: The lattice thermal conductivity of the newly synthesized 2D MoSi2N4 family was analyzed using ab initio phonon Boltzmann transport calculations. It was found that MoSi2N4 showed anomalous behavior in terms of thermal conductivity compared to other elements within the same group, deviating from the classic rule proposed by Slack.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Physics, Applied
Shukai Yao, Babak Anasori, Alejandro Strachan
Summary: 2D rare-earth metal carbides (MXenes) with novel electronic and magnetic properties and potential as scalable 2D magnets were investigated. The effect of the U parameter on the stability and magnetism of different termination sites was studied. It was found that Mo2NdC2O2 and Mo2NdC2(OH)(2) exhibited magnetic properties regardless of termination and Hubbard U value.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Zhen Tong, Traian Dumitrica, Thomas Frauenheim
Summary: Using first-principles calculations and theoretical framework, it was found that monolayer molybdenum trioxide has record low thermal conductivity due to soft flexural and in-plane acoustic modes combined with strong bonding anharmonicity. These insights can guide the search for 2D materials with low thermal conductivity and motivate measurements for potential applications in thermoelectricity and thermal protection.
Article
Computer Science, Interdisciplinary Applications
Marti Raya-Moreno, Xavier Cartoixa, Jesus Carrete
Summary: We introduce BTE-Barna, a software package that extends the MC module of the almaBTE solver for phonon transport in nanosystems based on 2D materials. It incorporates the propagator for the full linearized version of the PBTE, allowing accurate modeling of scattering-induced phonon occupation evolution in momentum space. The code can find solutions for finite and extended devices with thermal gradients, isothermal reservoirs, or arbitrary initial temperature distributions, providing temperature and heat flux distributions as well as their spectral decompositions.
COMPUTER PHYSICS COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Zizhen Zhou, Xiaolong Yang, Huixia Fu, Rui Wang, Xu Lu, Guoyu Wang, Xiaoyuan Zhou
Summary: In 2D semiconductor hexagonal boron phosphorus, electron-phonon coupling can be significantly enhanced or dominant through doping, leading to a significant reduction in lattice thermal conductivity. This unique phenomenon is attributed to the joint effects of horizontal mirror symmetry breaking and weak phonon-phonon scattering.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Wenyu Huang, Liying Hou, Yang Song, Gang Chen
Summary: Our calculations suggest that assembly of dehydrogenated pyracyclene molecules can produce novel graphene allotropes with high stabilities. The allotropes exhibit different properties, including a Dirac semimetal with tunable velocities of the massless Fermion carriers and a semiconducting material with a 1.20 eV band gap and high charge carrier mobilities. These allotropes could be used in next-generation nanoelectronics and as photovoltaic materials. Additionally, stacked layers of the allotropes show potential as anodes for lithium-ion batteries.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Wenyu Huang, Liying Hou, Yang Song, Gang Chen
Summary: Our first-principles calculations suggest the assembly of dehydrogenated pyracyclene molecules can form novel graphene allotropes with high stabilities. These allotropes have the potential for various applications, such as photovoltaic materials, next-generation nanoelectronics, and lithium-ion battery anodes.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Hang Lyu, Wilwin Wilwin, Zhenyang Lin, Haibin Su
Summary: This study identifies the important role of the gauche conformation in the energetics of monolayer phosphorus allotropes. The stability of phosphorene allotropes is closely related to the delicate interactions of lone pairs manifested by the gauche effect.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Computer Science, Interdisciplinary Applications
Abhishek Pathak, Avinash Pawnday, Aditya Prasad Roy, Amjad J. Aref, Gary F. Dargush, Dipanshu Bansal
Summary: MCBTE is an algorithm that solves the linearized Boltzmann transport equation for phonons in three dimensions, suitable for analyzing thermal transport in structured materials in both transient and steady-state scenarios. The program outputs temperature and heat flux, allowing the study of cumulative thermal conductivity.
COMPUTER PHYSICS COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Jianye Liu, Yinchang Zhao, Zhenhong Dai, Jun Ni, Sheng Meng
Summary: Thermoelectric property involves the conversion of thermal energy into electrical energy via Seebeck effect. This study focused on the thermal transport and thermoelectric properties of crystalline mercury chalcogenides, revealing that semiconducting mercury chalcogenides exhibit good thermoelectric performance due to low thermal conductivity and high power factors. In contrast, the lattice thermal conductivity of semimetallic mercury chalcogenides is higher, limiting their applications in thermoelectricity.
COMPUTATIONAL MATERIALS SCIENCE
(2021)
Article
Physics, Condensed Matter
Lijun Pan, Jesus Carrete, Zhao Wang
Summary: In this study, the effect of biaxial tensile strain on phonon transport in a Janus PtSTe monolayer was investigated using first-principles calculations and Boltzmann transport theory. It was found that the lattice thermal conductivity decreases nonlinearly with increasing strain, reaching close to an order of magnitude reduction when the band gap disappears completely under high strains (>8%). This behavior is attributed to a strong enhancement of anharmonic scattering of acoustic phonons due to the band overlap.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Chemistry, Multidisciplinary
Di Yang, Chunyu Zhao, Ruqian Lian, Lin Yang, Yizhan Wang, Yu Gao, Xu Xiao, Yury Gogotsi, Xudong Wang, Gang Chen, Yingjin Wei
Summary: A method for achieving planar, dendrite-free Li metal growth on Ti3C2Tx MXene is reported, overcoming the barrier of irregular and nonplanar electrodeposition of Li. The prepared Li metal anode demonstrates stable cycling and high capacity retention, making it promising for application in Li metal batteries.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Juan J. J. Aucar, Alejandro F. F. Maldonado, Juan I. I. Melo
Summary: In this work, relativistic corrections to the electric field gradient (EFG) are presented, including spin-dependent corrections for the first time. The results show that these new corrections significantly improve the performance of the existing method and are in close agreement with calculations at the four-component Dirac-Hartree-Fock (4c-DHF) level. The accuracy of the EFG values obtained with this new method allows for the analysis of the electronic origin of relativistic effects using well-known nonrelativistic operators.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Pradip Nandi, Abir De Sarkar
Summary: This study predicts and explores the potential nontoxic 2D SnNBr system through experimental synthesis and theoretical investigations. The system exhibits stability, direct bandgap, and high carrier mobility. Furthermore, it possesses high out-of-plane piezoelectricity and shows positive clamped-ion contribution to piezoelectricity, which is different from the usual response in bulk materials. The tunability of these properties with the number of layers is also emphasized.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Cheng Tang, Lei Zhang, Stefano Sanvito, Aijun Du
Summary: A general strategy for achieving 2D triferroicity by imposing electric polarization into a ferroelastic magnet is proposed in this study, and dual transition-metal dichalcogenides, such as 1T'-CrCoS4, are demonstrated to display room temperature triferroicity. The 1T'-CrCoS4 monolayer shows negative out-of-plane piezoelectricity and strain-tunable magnetic anisotropy, making it a strong candidate for practical applications. This research introduces a new class of 2D room-temperature triferroic materials, providing a promising platform for advanced spintronics.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Jiayi Li, Xin Mao, Wanbing Gong, Xinyu Wang, Yawen Jiang, Ran Long, Aijun Du, Yujie Xiong
Summary: A simple and scalable electro-deposition and subsequent phosphorization route was developed to fabricate Ni-doped Co2P nanosheets catalyst using the in-situ released Ni species from defective Ni foam as metal source. The as-synthesized Ni-Co2P catalyst exhibited excellent electrochemical 5-hydroxymethylfurfural oxidation reaction (HOR) performance with high yield and Faradaic efficiency. By coupling the electrocatalytic HOR with hydrogen evolution reaction (HER), a low cell voltage was achieved for driving a high current density, providing a facile and efficient approach for the concurrent production of H2 and value-added chemicals.
Article
Chemistry, Physical
Jiangfeng Yuan, Hanqing Yin, Xiaoxin Jin, Dan Zhao, Yuan Liu, Aijun Du, Xiaoqiang Liu, Anthony P. O'Mullane
Summary: The conversion of nitrite ions into ammonia via an electrochemical process is significant due to its potential in addressing the energy-intensive ammonia production and substantial environmental pollution caused by nitrite ions. A study successfully prepared iron phosphide nanoarrays on a Ti plate and utilized it as an efficient catalyst for the conversion of nitrite ions into ammonia. The optimized parameters and mechanistic studies revealed that atomic hydrogen greatly influenced the reaction rate and selectivity, and specific facets of FeP were identified as the main active sites for nitrite reduction.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Physics, Applied
Cheng Tang, Aijun Du
Summary: Two-dimensional multiferroic materials are explored through structural design and molecular engineering for robust magnetoelectric coupling and controllable topological solitons. This review focuses on the design of multiferroic structures in the 2D form, achieving robust magnetoelectric coupling, and electrically controlling magnetic skyrmions via multiferroic effects. Challenges and opportunities for predicting 2D multiferroic materials are discussed.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Physical
Hanqing Yin, Xin Mao, Stuart Bell, Dmitri Golberg, Aijun Du
Summary: In this study, TM-free alloy catalysts based on indium and p-block elements were proposed for the electroreduction of nitrate to ammonia, showing an extraordinary performance. A novel reaction pathway was identified on the In3Sn(100) surface, with the free energy evolution going completely downhill. In addition, proton adsorption was found to be extremely weak on the In3Sn(100) surface, suppressing the parasitic hydrogen evolution reaction. The high activity and inhibition of the competing reaction contribute to the excellent performance of these p-block metal-based catalysts in NRA.
CHEMISTRY OF MATERIALS
(2023)
Article
Physics, Applied
Jiayi Li, Yanming Lin, Minjie Zhang, Ying Peng, Xinru Wei, Zhengkun Wang, Zhenyi Jiang, Aijun Du
Summary: Designing an efficient heterostructure for photocatalytic hydrogen production is of great significance in addressing the energy shortage and environmental crisis. This study investigates the structure, electron of interface, optical properties, charge transfer, and photocatalytic mechanism of three ZnIn2S4/alpha-In2Se3 heterostructures using density functional calculation. The results show that the presence of an external electric field can not only change the bandgap but also modulate the band alignment type. Among the three heterostructures, A is a type II heterostructure, while B and C are Z-scheme heterostructures, with heterostructure C demonstrating the importance of electrons on the conduction band maximum of a ZnIn2S4 monolayer in the hydrogen production process. Additionally, the small bandgap of ZnIn2S4/alpha-In2Se3 Z-scheme heterostructures allows for a wide light absorption range. Overall, this study contributes to the design of a novel and potential Z-scheme heterostructure photocatalyst with broad application prospects in both electronic and optoelectronic fields.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Hao Wu, Lei Zhang, Songying Qu, Aijun Du, Junwang Tang, Yun Hau Ng
Summary: Hydrogen dopants and oxygen vacancies are important in BiVO4 photoanodes, but the impact of hydrogenation on charge transport, particularly electron small polaron formation, is not well understood. This study demonstrates that mild hydrogenation of nanoporous BiVO4 reduces the charge transport barrier, as shown by thermally activating photocurrent responses. The hydrogen atoms occupy oxygen vacancies, reducing the activation energy and facilitating electron small polaron transport. A BiVO4 photoanode with NiFeOx cocatalyst achieves an applied-bias photon-to-current efficiency of 1.91% at 0.58 V vs RHE. This study expands the understanding of hydrogen doping beyond conventional donor density/surface chemisorption mediations to include small polaron hopping.
ACS ENERGY LETTERS
(2023)
Article
Chemistry, Physical
Fuhao Jin, Hanqing Yin, Ru Feng, Wei Niu, Wanting Zhang, Jingquan Liu, Aijun Du, Wenrong Yang, Zhen Liu
Summary: In this study, a core-shell nanostructure of polypyrrole (PPy) coated sulfur-doped iron oxide nanoparticles (S-Fe2O3@PPy) is prepared as highly selective and durable electrocatalysts for N-2 reduction reaction (NRR). Sulfur doping and PPy coating greatly enhance the charge transfer efficiency and produce abundant oxygen vacancies as active sites for NRR. The catalyst achieves a NH3 production rate of 22.1 μg/h(mg(cat)) and a very-high Faradic efficiency of 24.6%, surpassing other Fe2O3 based NRR catalysts. Density functional theory calculations demonstrate that the S-coordinated iron site can activate the N-2 molecule and optimize the energy barrier during the reduction process, leading to a small theoretical limiting potential.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Minh Tam Hoang, Chen Han, Zhipeng Ma, Xin Mao, Yang Yang, Sepideh Sadat Madani, Paul Shaw, Yongchao Yang, Lingyi Peng, Cui Ying Toe, Jian Pan, Rose Amal, Aijun Du, Tuquabo Tesfamichael, Zhaojun Han, Hongxia Wang
Summary: The low phase stability of metal halide perovskite catalysts limits their application in CO2 reduction reaction (CO2RR). In this study, a reduced graphene oxide (rGO) wrapped CsPbI3 perovskite nanocrystal (NC) CO2RR catalyst (CsPbI3/rGO) showed enhanced stability in the aqueous electrolyte and exhibited >92% Faradaic efficiency toward formate production. The superior performance of the CsPbI3/rGO catalyst was attributed to the synergistic effects between the CsPbI3 NCs and rGO, which stabilized the alpha-CsPbI3 phase and tuned the charge distribution.
NANO-MICRO LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Muhammad Ahmed, Gurpreet Kour, Ziqi Sun, Aijun Du, Xin Mao
Summary: The hydrogen evolution reaction (HER) is a notable mechanism for hydrogen production through water electrolysis. However, the use of noble metal catalysts like platinum presents limitations in terms of availability and cost. In this study, we demonstrated the effectiveness of aryl-functionalised catalysts on single-walled carbon nanotubes (SWCNTs) for the HER using density functional theory (DFT) calculations. We found that the curvature of the nanotubes and the proposed aryl-functionalised catalysts have a significant impact on the HER performance.
Article
Chemistry, Inorganic & Nuclear
Hanqing Yin, Stuart Bell, Dmitri Golberg, Aijun Du
Summary: Currently, the Haber-Bosch (HB) process dominates artificial ammonia synthesis. However, concerns over energy consumption and air pollution have led to a growing demand for economical and eco-friendly approaches like electrocatalysis. Through density functional theory calculations, we investigated bimetallic alloys of iron and group-IVA elements for their potential in electrochemical nitrogen reduction reaction (e-N2RR). Our findings showed that alloying iron with group-IVA elements can significantly enhance the e-N2RR activity, with an optimal Fe-Si ratio of 3:1 yielding a theoretical overpotential of only 0.21 V, one of the best results observed. Our work proposes a rational design for practical and economical e-N2RR electrocatalysts, as many of the bimetallic alloys studied have already been synthesized.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Xiaoyan Miao, Si Li, Zhenyi Jiang, Chunmei Zhang, Aijun Du
Summary: By using density functional theory, we investigated the crystalline configuration and electronic structure of the Fe3GeTe2 monolayer under external strain. We found that a moderate compressive strain can break the structural vertical symmetry while retaining the ferromagnetism. Surprisingly, strain-induced polarization in the off-center Fe and Ge atoms barely contributes to the energy states at the Fermi level. The decoupling of conductivity and polarization in the strained Fe3GeTe2 monolayer results in a rare phase with the coexistence of polarization, metallicity, and ferromagnetism, known as magnetic polar metals, which have potential applications in magnetoelectricity and spintronics.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Hongbo Wu, Fengxian Ma, Zhixue Tian, Ying Liu, Yalong Jiao, Aijun Du
Summary: Using first-principles calculations, we predict that two ferromagnetic monolayers, BiXO3 (X = Ru, Os), have direct band gaps and high Curie temperatures. Monte Carlo simulations show that the monolayers exhibit high Tc beyond 400 K. Both monolayers demonstrate out-of-plane magnetic anisotropy, with significant magnetic anisotropy energies. The electronic and magnetic properties of BiXO3 monolayers make them promising candidates for nanoscale electronics and spintronics.
Article
Chemistry, Multidisciplinary
Huijie Liu, Mengnan Qu, Aijun Du, Qiao Sun
Summary: Through DFT calculations, the study demonstrates that uranium-doped C2N/C3N4 monolayers can strongly embed uranium atoms and allow for strong adsorption of N-2 on the surfaces with adsorption energies ranging from -0.69 to -0.98 eV. The NH3 formation process on these catalysts has relatively low limiting potentials, especially for uranium-doped C2N (-0.44 V). Additionally, the study shows that nitrogen reduction reaction (NRR) is predominant over competing hydrogen evolution reaction (HER) on the uranium-doped substrates.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Lei Zhang, Cheng Tang, Stefano Sanvito, Aijun Du
Summary: A new concept of highly degenerate ferroelectricity with multiple FE states coexisting in a single 2D material is proposed through the asymmetrical decoration of porous COFs/MOFs. First-principles calculations and MC simulations reveal that Li-decorated 2D Cr(pyz)(2) is a prototype of highly degenerate 2D FE materials, showing four-fold and eight-fold degenerate ferroelectricity. Three-fold and six-fold degenerate ferroelectricity is also demonstrated in P-decorated g-C3N4 and Ru-decorated C2N, respectively. This work presents a general route to obtain highly degenerate 2D ferroelectricity, expanding the applications of 2D FE compounds.
MATERIALS HORIZONS
(2023)