Quantum confinement effect and reduced dielectric screening in two-dimensional(2D)dramatically enhance theelectron-hole interactions.In this work,we use many-body perturbation theory and Bethe-Salpeter equation(BSE)to...Quantum confinement effect and reduced dielectric screening in two-dimensional(2D)dramatically enhance theelectron-hole interactions.In this work,we use many-body perturbation theory and Bethe-Salpeter equation(BSE)toinvestigate the electronic and excitonic optical properties of monolayer SnP_(2)S_(6).Our findings reveal that the excitoniceffect dominates the optical absorption spectra in the visible light range,and the lowest-energy exciton X0 in monolayerSnP_(2)S_(6)is optically bright with the binding energy of 0.87 eV and the radiative lifetime of~10^(-11)s,which is highly advantageousto the photo-luminescence.Most importantly,the absence of optically forbidden states below the bright statesX0 would give rise to a high quantum efficiency of 2D SnP_(2)S_(6).We also find that applied biaxial strain can further shortenthe radiative lifetime of the bright states.These results imply that 2D SnP_(2)S_(6)is a promising candidate for the optoelectronicdevices.展开更多
Copper indium thiophosphate,CuInP_(2)S_(6),has attracted much attention in recent years due to its van der Waals layered structure and robust ferroelectricity at room temperature.In this review,we aim to give an overv...Copper indium thiophosphate,CuInP_(2)S_(6),has attracted much attention in recent years due to its van der Waals layered structure and robust ferroelectricity at room temperature.In this review,we aim to give an overview of the various properties of CuInP_(2)S_(6),covering structural,ferroelectric,dielectric,piezoelectric and transport properties,as well as its potential applications.We also highlight the remaining questions and possible research directions related to this fascinating material and other compounds of the same family.展开更多
Free vibration of elastically constrained rectangular single-layered M0S_(2)is investigated by using a nonlocal Kirchhoff plate model with an initial stress.The variationally consistent elastically constrained boundar...Free vibration of elastically constrained rectangular single-layered M0S_(2)is investigated by using a nonlocal Kirchhoff plate model with an initial stress.The variationally consistent elastically constrained boundary conditions are obtained by using the weighted residual method,while the governing equations of the nonlocal Kirchhoff plate model are known.A modified Fourier series method is applied to study the vibrational behaviors of elastically constrained nonlocal Kirchhoff plate models.The convergence and reliability of the modified Fourier series method is verified via comparison with the finite element method.A comprehensive parametric study is performed to show the influences of the boundary elastic constant,nonlocal parameter and initial stress on the vibrational behaviors of single-layered M0S2.The results should be good for the design of nanoresonators.展开更多
Low-concentration Au(S_(2)O_(3))2^(3-)recovery is an urgent issue to facilitate the application of thiosulfate leaching instead of cyanide leaching in factories.Herein,this work presents a novel recovery of low-concen...Low-concentration Au(S_(2)O_(3))2^(3-)recovery is an urgent issue to facilitate the application of thiosulfate leaching instead of cyanide leaching in factories.Herein,this work presents a novel recovery of low-concentration Au(S_(2)O_(3))2^(3-) combining adsorption and electrodeposition(electroreduction)to realize high Au(S_(2)O_(3))2^(3-)recovery in the form of gold particles(Au^(0)).Walnut shells were used as the raw material for the successful preparation of charcoal with porous structure and rich oxygen-containing functional groups.Walnut shell charcoal(WSC)as the electrode achieved efficient recovery of low-concentration Au(S_(2)O_(3))2^(3-).The recovery under low-concentration conditions was higher than 90%,with the highest reduction of 46.97 mg·g^(-1).Applying a suitable low voltage(0.8 V)facilitated lowconcentration Au(S_(2)O_(3))2^(3-)recovery,which was immensely improved than that without voltage.Au(S_(2)O_(3))2^(3-)recovery performances under applied voltage via the WSC electrode were related to electrochemical abilities,including reaction intensity and charge transfer.More reactive sites containing suitable pores and oxygen functional groups were beneficial for the reduction reaction.This work offers a new way to recover low-concentration Au(S_(2)O_(3))2^(3-)via cheap charcoal electrodes from solutions for application in the cyanide-free leaching method in industry.展开更多
基金support by the National Natural Science Foundation of China(Grant No.12064032).
文摘Quantum confinement effect and reduced dielectric screening in two-dimensional(2D)dramatically enhance theelectron-hole interactions.In this work,we use many-body perturbation theory and Bethe-Salpeter equation(BSE)toinvestigate the electronic and excitonic optical properties of monolayer SnP_(2)S_(6).Our findings reveal that the excitoniceffect dominates the optical absorption spectra in the visible light range,and the lowest-energy exciton X0 in monolayerSnP_(2)S_(6)is optically bright with the binding energy of 0.87 eV and the radiative lifetime of~10^(-11)s,which is highly advantageousto the photo-luminescence.Most importantly,the absence of optically forbidden states below the bright statesX0 would give rise to a high quantum efficiency of 2D SnP_(2)S_(6).We also find that applied biaxial strain can further shortenthe radiative lifetime of the bright states.These results imply that 2D SnP_(2)S_(6)is a promising candidate for the optoelectronicdevices.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.11904176,61874060,61911530220,U1932159,11774249)the Natural Science Foundation of Jiangsu Higher Education Institutions(Grant No.19KJB140004)+2 种基金the startup found from NJUPT(Grant Nos.NY219028,NY217118)NSF of Jiangsu Province(Grant Nos.BK20181388,BK20171209)the Key University Science Research Project of Jiangsu Province(Grant No.18KJA140004)。
文摘Copper indium thiophosphate,CuInP_(2)S_(6),has attracted much attention in recent years due to its van der Waals layered structure and robust ferroelectricity at room temperature.In this review,we aim to give an overview of the various properties of CuInP_(2)S_(6),covering structural,ferroelectric,dielectric,piezoelectric and transport properties,as well as its potential applications.We also highlight the remaining questions and possible research directions related to this fascinating material and other compounds of the same family.
基金We gratefully acknowledge the support from the Natural Science Foundation of Chongqing(cstc2020jcyj-msxmX0037)State Key Laboratory of Mechanics and Control of Mechanical Structures(Nanjing University of Aeronautics and astronautics)under Grants MCMS-E-0120G01National Natural Science Foundation of China under Grants Nos.11925205 and 51921003,and the Fundamental Research Funds for the Central Universities of China.
文摘Free vibration of elastically constrained rectangular single-layered M0S_(2)is investigated by using a nonlocal Kirchhoff plate model with an initial stress.The variationally consistent elastically constrained boundary conditions are obtained by using the weighted residual method,while the governing equations of the nonlocal Kirchhoff plate model are known.A modified Fourier series method is applied to study the vibrational behaviors of elastically constrained nonlocal Kirchhoff plate models.The convergence and reliability of the modified Fourier series method is verified via comparison with the finite element method.A comprehensive parametric study is performed to show the influences of the boundary elastic constant,nonlocal parameter and initial stress on the vibrational behaviors of single-layered M0S2.The results should be good for the design of nanoresonators.
基金supported by the National Key Research and Development Program of China (No.2021YFC2900900)。
文摘Low-concentration Au(S_(2)O_(3))2^(3-)recovery is an urgent issue to facilitate the application of thiosulfate leaching instead of cyanide leaching in factories.Herein,this work presents a novel recovery of low-concentration Au(S_(2)O_(3))2^(3-) combining adsorption and electrodeposition(electroreduction)to realize high Au(S_(2)O_(3))2^(3-)recovery in the form of gold particles(Au^(0)).Walnut shells were used as the raw material for the successful preparation of charcoal with porous structure and rich oxygen-containing functional groups.Walnut shell charcoal(WSC)as the electrode achieved efficient recovery of low-concentration Au(S_(2)O_(3))2^(3-).The recovery under low-concentration conditions was higher than 90%,with the highest reduction of 46.97 mg·g^(-1).Applying a suitable low voltage(0.8 V)facilitated lowconcentration Au(S_(2)O_(3))2^(3-)recovery,which was immensely improved than that without voltage.Au(S_(2)O_(3))2^(3-)recovery performances under applied voltage via the WSC electrode were related to electrochemical abilities,including reaction intensity and charge transfer.More reactive sites containing suitable pores and oxygen functional groups were beneficial for the reduction reaction.This work offers a new way to recover low-concentration Au(S_(2)O_(3))2^(3-)via cheap charcoal electrodes from solutions for application in the cyanide-free leaching method in industry.
