It is known that exposed surface determines material’s performance.WO3 is widely used in gas sensing and its working surface is proposed to control its sensitivity.However,the working surface,or most exposed surface ...It is known that exposed surface determines material’s performance.WO3 is widely used in gas sensing and its working surface is proposed to control its sensitivity.However,the working surface,or most exposed surface with detailed surface structure remain unclear.In this paper,DFT calculation confirmed that oxygen vacancy O-terminated surface is the most exposed hexagonal WO3(001)surface,judging from competitive adsorption of CO and O2,working surface determination for CO sensing and comparison of oxygen vacancy formation ene rgies on different h-WO3(001)surfaces.It is found that DFT can be a useful alternate for exposed surface determination.Our results provide new perspectives and performance explanations for material research.展开更多
Hybrid density functional calculations was used to comprehensively study the electronic structure of S-,Snand Pb-monodoped and（Sn,S）-and（Pb,S）-codoped hexagonal WO_3（h-WO_3）in order to improve their visible ligh...Hybrid density functional calculations was used to comprehensively study the electronic structure of S-,Snand Pb-monodoped and（Sn,S）-and（Pb,S）-codoped hexagonal WO_3（h-WO_3）in order to improve their visible light photocatalytic activity.Results indicate that the（Sn,S）-and（Pb,S）-codoped h-WO_3 can realize a significant band gap reduction and prevent the formation of empty states in the valence band of h-WO_3,while Sn/Pb-monodoped h-WO_3 cannot,because in（Sn,S）-and（Pb,S）-codoping,the S-doping introduces the fully occupied S 3p states in the forbidden band gap of h-WO_3 and the acceptor metals（Sn and Pb）would assist the coupling of the introduced S with its nearest O.In particular,the（Sn,S）-codoped h-WO_3 has the narrowest band gap of 1.85 eV and highest reducing ability among the doped case.Moreover,the calculated optical absorption spectra show that（Sn,S）-codoping can improve the visible light absorption.In short,these results indicate that the（Sn,S）-codoped h-WO_3 is a promising material in solar-driven water splitting.展开更多
基金supported by National Natural Science Foundation of China(Nos.61971252,20703027)Excellent Youth Fund of Shandong Province(No.ZR201709200070)+2 种基金Foundation of Shandong Educational Committee(No.J09LB06)Shandong excellent young scientist research award fund(No.BS2011NJ004)open project of Shanghai Key Laboratory of Rare Earth Functional Materials。
文摘It is known that exposed surface determines material’s performance.WO3 is widely used in gas sensing and its working surface is proposed to control its sensitivity.However,the working surface,or most exposed surface with detailed surface structure remain unclear.In this paper,DFT calculation confirmed that oxygen vacancy O-terminated surface is the most exposed hexagonal WO3(001)surface,judging from competitive adsorption of CO and O2,working surface determination for CO sensing and comparison of oxygen vacancy formation ene rgies on different h-WO3(001)surfaces.It is found that DFT can be a useful alternate for exposed surface determination.Our results provide new perspectives and performance explanations for material research.
基金supported by the National Natural Science Foundation of China (21476024, 21576008, 91334203 and 91634116)the National Key Technology Support Program (2014BAE12B01)+2 种基金Beijing Municipal Science and Technology Project (Z151100003315005)the Fundamental Research Funds for the Central Universities (PYCC1705)the “Chemical Grid Project” of BUCT
文摘Hybrid density functional calculations was used to comprehensively study the electronic structure of S-,Snand Pb-monodoped and（Sn,S）-and（Pb,S）-codoped hexagonal WO_3（h-WO_3）in order to improve their visible light photocatalytic activity.Results indicate that the（Sn,S）-and（Pb,S）-codoped h-WO_3 can realize a significant band gap reduction and prevent the formation of empty states in the valence band of h-WO_3,while Sn/Pb-monodoped h-WO_3 cannot,because in（Sn,S）-and（Pb,S）-codoping,the S-doping introduces the fully occupied S 3p states in the forbidden band gap of h-WO_3 and the acceptor metals（Sn and Pb）would assist the coupling of the introduced S with its nearest O.In particular,the（Sn,S）-codoped h-WO_3 has the narrowest band gap of 1.85 eV and highest reducing ability among the doped case.Moreover,the calculated optical absorption spectra show that（Sn,S）-codoping can improve the visible light absorption.In short,these results indicate that the（Sn,S）-codoped h-WO_3 is a promising material in solar-driven water splitting.
