Based on the density functional theory,the double half-Heusler alloys LuXCo_(2)Bi_(2)(X=V,Nb,and Ta)were studied to predict their structural,thermodynamic,thermoelectric,and optical characteristics.All the considered ...Based on the density functional theory,the double half-Heusler alloys LuXCo_(2)Bi_(2)(X=V,Nb,and Ta)were studied to predict their structural,thermodynamic,thermoelectric,and optical characteristics.All the considered alloys are thermodynamically stable and have semiconductor behavior with indirect band gaps of 0.62,0.75,and 0.8 eV for LuVCo_(2)Bi_(2),LuNbCo_(2)Bi_(2),and LuTaCu_(2)Bi_(2),respectively.The investigated compounds exhibit semiconducting behavior with energy gaps below 0.8 eV.The impact of heat and pressure on thermodynamic coefficients was evaluated,and the influence of charge carriers on the temperature-dependent properties was studied using the semi-classical Boltzmann model.The studied compounds were characterized by their low lattice thermal conductivity at room temperature and low thermal expansion coefficient.These alloys exhibit substantial absorption coefficients in the ultraviolet(UV)light region,high optical conductivity,and high reflectivity in the visible light region,making them highly appealing materials for applications in the energy and electronics sectors.展开更多
The polysulfide shuttling effect is the primary bottleneck restricting the industrial application of Li-S batteries,and the electrocatalytic sulfur reduction reaction(SRR)has emerged as an effective solution.Carbon-ba...The polysulfide shuttling effect is the primary bottleneck restricting the industrial application of Li-S batteries,and the electrocatalytic sulfur reduction reaction(SRR)has emerged as an effective solution.Carbon-based singleatom catalysts(SACs),which promotes SRR,show great potential in inhibiting the shuttling effect of polysulfides.Meanwhile,the optimization and rational design of such catalysts requires a deep understanding to the fundamental SRR mechanism and remains highly nontrivial.In this work,we construct a comprehensive database of carbon-based SACs,covering different coordination patterns,heteroatoms,and transition metals.The SRR activities are determined using density functional theory calculations,revealing a synergistic effect between the p orbital of the heteroatom and the d orbital of the transition metal.This interplay underscores the critical importance of the coordination environment for SRR under the ortho-P_(2)C_(2)structure.Regardless of the transition metal type,the ortho-P_(2)C_(2)coordination pattern significantly enhances the SRR performance of SACs,surpassing the widely reported N_(3)C_(1)and N_(4)coordinated graphene-based SACs.Furthermore,heteroatoms with ortho-P_(2)C_(2)may exhibit SRR activity.In a word,by using this comprehensive dataset and data-driven framework,we propose a promising novel class of coordination structure(ortho-P_(2)C_(2)structure)and neglected design principle.展开更多
文摘Based on the density functional theory,the double half-Heusler alloys LuXCo_(2)Bi_(2)(X=V,Nb,and Ta)were studied to predict their structural,thermodynamic,thermoelectric,and optical characteristics.All the considered alloys are thermodynamically stable and have semiconductor behavior with indirect band gaps of 0.62,0.75,and 0.8 eV for LuVCo_(2)Bi_(2),LuNbCo_(2)Bi_(2),and LuTaCu_(2)Bi_(2),respectively.The investigated compounds exhibit semiconducting behavior with energy gaps below 0.8 eV.The impact of heat and pressure on thermodynamic coefficients was evaluated,and the influence of charge carriers on the temperature-dependent properties was studied using the semi-classical Boltzmann model.The studied compounds were characterized by their low lattice thermal conductivity at room temperature and low thermal expansion coefficient.These alloys exhibit substantial absorption coefficients in the ultraviolet(UV)light region,high optical conductivity,and high reflectivity in the visible light region,making them highly appealing materials for applications in the energy and electronics sectors.
基金supported by the Scientific Research Start-up Funds of Tsinghua SIGS(QD2021018C to Peng L)the National Natural Science Foundation of China(20231710015 and 22209096 to Peng L)+2 种基金GuangDong Basic and Applied Basic Research Foundation(2023A1515010059 to Peng L)Shenzhen Fundamental Research Program(JCYJ20220530143003008 to Peng L)Shenzhen Science and Technology Program(ZDSYS20230626091100001)。
文摘The polysulfide shuttling effect is the primary bottleneck restricting the industrial application of Li-S batteries,and the electrocatalytic sulfur reduction reaction(SRR)has emerged as an effective solution.Carbon-based singleatom catalysts(SACs),which promotes SRR,show great potential in inhibiting the shuttling effect of polysulfides.Meanwhile,the optimization and rational design of such catalysts requires a deep understanding to the fundamental SRR mechanism and remains highly nontrivial.In this work,we construct a comprehensive database of carbon-based SACs,covering different coordination patterns,heteroatoms,and transition metals.The SRR activities are determined using density functional theory calculations,revealing a synergistic effect between the p orbital of the heteroatom and the d orbital of the transition metal.This interplay underscores the critical importance of the coordination environment for SRR under the ortho-P_(2)C_(2)structure.Regardless of the transition metal type,the ortho-P_(2)C_(2)coordination pattern significantly enhances the SRR performance of SACs,surpassing the widely reported N_(3)C_(1)and N_(4)coordinated graphene-based SACs.Furthermore,heteroatoms with ortho-P_(2)C_(2)may exhibit SRR activity.In a word,by using this comprehensive dataset and data-driven framework,we propose a promising novel class of coordination structure(ortho-P_(2)C_(2)structure)and neglected design principle.
