GeTe has attracted extensive research interest for thermoelectric applications.In this paper,we first train a neuroevolution potential(NEP)based on a dataset constructed by ab initio molecular dynamics,with the Gaussi...GeTe has attracted extensive research interest for thermoelectric applications.In this paper,we first train a neuroevolution potential(NEP)based on a dataset constructed by ab initio molecular dynamics,with the Gaussian approximation potential(GAP)as a reference.The phonon density of states is then calculated by two machine learning potentials and compared with density functional theory results,with the GAP potential having higher accuracy.Next,the thermal conductivity of a GeTe crystal at 300 K is calculated by the equilibrium molecular dynamics method using both machine learning potentials,and both of them are in good agreement with the experimental results;however,the calculation speed when using the NEP potential is about 500 times faster than when using the GAP potential.Finally,the lattice thermal conductivity in the range of 300 K-600 K is calculated using the NEP potential.The lattice thermal conductivity decreases as the temperature increases due to the phonon anharmonic effect.This study provides a theoretical tool for the study of the thermal conductivity of GeTe.展开更多
Single-atom catalysts(SACs)hold great promise in addressing the sluggish kinetics of the sulfur reduction reaction(SRR)in lithium-sulfur(Li-S)batteries for their unique catalytic activity and maximum atom efficiency.W...Single-atom catalysts(SACs)hold great promise in addressing the sluggish kinetics of the sulfur reduction reaction(SRR)in lithium-sulfur(Li-S)batteries for their unique catalytic activity and maximum atom efficiency.While these SACs must be dispersed on solid substrates,the underlying support is usually limited to carbon materials that have a poor ability to modulate the coordination environment and electronic structures of single atoms,and consequently their catalytic activity toward the SRR is restricted.Here we propose two-dimensional(2D)graphene/electride heterostructu res as substrates to enhance the catalytic activities of SACs for Li-S batteries.2D electrides featuring the anionic electron gas on their surface enable efficient electron transfer to SACs,which alters their electronic structures,resulting in the shifts of the d orbital and Fermi levels.This unique electronic structure decreases the filling of antibonding states such that the bonding with adsorbates at active sites is enhanced.We demonstrate the enhanced catalytic performance of SACs in terms of the Gibbs free energy of SRR and Li_(2)S dissociation.In addition,a universal descriptor for the rapid screening of SACs is established by a linear regression fitting method.This work provides a new design strategy to modulate SAC activity through electrides for Li-S batteries.展开更多
基金Project supported by the A*STAR Computational Resource Centre through the use of its high-performance computing facilitiesfinancial support from the China Scholarship Council (Grant No.202206120136)。
文摘GeTe has attracted extensive research interest for thermoelectric applications.In this paper,we first train a neuroevolution potential(NEP)based on a dataset constructed by ab initio molecular dynamics,with the Gaussian approximation potential(GAP)as a reference.The phonon density of states is then calculated by two machine learning potentials and compared with density functional theory results,with the GAP potential having higher accuracy.Next,the thermal conductivity of a GeTe crystal at 300 K is calculated by the equilibrium molecular dynamics method using both machine learning potentials,and both of them are in good agreement with the experimental results;however,the calculation speed when using the NEP potential is about 500 times faster than when using the GAP potential.Finally,the lattice thermal conductivity in the range of 300 K-600 K is calculated using the NEP potential.The lattice thermal conductivity decreases as the temperature increases due to the phonon anharmonic effect.This study provides a theoretical tool for the study of the thermal conductivity of GeTe.
基金financially supported by the National Natural Science Foundation of China (No.22209196 and 12247167)Shandong Province through the Taishan Scholar Programthe Technological Innovation Project (MSTIP) (No.2019JZZY010209)。
文摘Single-atom catalysts(SACs)hold great promise in addressing the sluggish kinetics of the sulfur reduction reaction(SRR)in lithium-sulfur(Li-S)batteries for their unique catalytic activity and maximum atom efficiency.While these SACs must be dispersed on solid substrates,the underlying support is usually limited to carbon materials that have a poor ability to modulate the coordination environment and electronic structures of single atoms,and consequently their catalytic activity toward the SRR is restricted.Here we propose two-dimensional(2D)graphene/electride heterostructu res as substrates to enhance the catalytic activities of SACs for Li-S batteries.2D electrides featuring the anionic electron gas on their surface enable efficient electron transfer to SACs,which alters their electronic structures,resulting in the shifts of the d orbital and Fermi levels.This unique electronic structure decreases the filling of antibonding states such that the bonding with adsorbates at active sites is enhanced.We demonstrate the enhanced catalytic performance of SACs in terms of the Gibbs free energy of SRR and Li_(2)S dissociation.In addition,a universal descriptor for the rapid screening of SACs is established by a linear regression fitting method.This work provides a new design strategy to modulate SAC activity through electrides for Li-S batteries.
