Prediction of Novel <i>p</i>‐Type Transparent Conductors in Layered Double Perovskites: A First‐Principles Study

Abstract

Abstract The development of high‐performance transparent conductors (TCs) is critical to various technologies from transparent electronics to solar cells. Whereas n ‐type TCs have been extensively applied in many electronic devices, their p ‐type counterparts have not been largely commercialized due to the lack of ideal materials. Combining atomic replacement and first‐principles calculations, seven stable layered double perovskites are identified, i.e., Cs 4 CuSb 2 Cl 12 ‐like Cs 4 M 2+ B 3+ 2 X VII 12 compounds as promising p ‐type TCs with sufficiently large bandgaps, delocalized wavefunction distribution with s ‐orbital components in valence band maximum (VBM) and the antibonding character of VBM to ensure their optical transparency, light hole effective masses, and intrinsic good p ‐type conductivities, respectively. Taking Cs 4 CdSb 2 Cl 12 as a representative example, it is demonstrated that under Cd‐poor (Cl‐rich) conditions, Cs 4 CdSb 2 Cl 12 could exhibit excellent p ‐type conductivity with high hole concentration, contributed by the intrinsic shallow‐acceptor Cd Sb with extremely low formation energy. Generally, the other 6 Cs 4 M 2+ B 3+ 2 X VII 12 compounds exhibit similar intrinsic p ‐type defect properties as Cs 4 CdSb 2 Cl 12 , which could rank them as the top p ‐type TCs discovered or predicted until now.