How Does Chemistry Influence Electron Effective Mass in Oxides? A High-Throughput Computational Analysis

Abstract

Many technologies require oxides with high electronic conductivity or mobility (e.g., transparent conducting oxides, oxide photovoltaics, or photocatalysis). Using high-throughput ab initio computing, we screen more than 4000 binary and ternary oxides to identify the compounds with the lowest electron effective mass. We identify 74 promising oxides and suggest a few novel potential n-type transparent conducting oxides combining a large band gap to a low effective mass. Our analysis indicates that it is unlikely to find oxides with electron effective masses significantly lower than the current high-mobility binary oxides (e.g., ZnO and In 2 O 3 ). Using the large data set, we extract chemical rules leading to low electron effective masses in oxides. Main group elements with ( n –1)d 10 n s 0 n p 0 cations in the rows 4 and 5 and groups 12–15 of the periodic table (i.e., Zn 2+, Ga 3+, Ge 4+, Cd 2+, In 3+, Sn 4+, and Sb 5+ ) induce the lowest electron effective masses because of their s orbitals hybridizing adequately with oxygen. More surprisingly, oxides containing 3d transition metals in a low oxidation state (e.g., Mn 2+ ) show also competitive effective masses due to the s character of their conduction band.