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

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., Cs₄CuSb₂Cl₁₂‐like Cs₄M²⁺B³⁺₂X^VII₁₂ 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 Cs₄CdSb₂Cl₁₂ as a representative example, it is demonstrated that under Cd‐poor (Cl‐rich) conditions, Cs₄CdSb₂Cl₁₂ 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 Cs₄M²⁺B³⁺₂X^VII₁₂ compounds exhibit similar intrinsic p‐type defect properties as Cs₄CdSb₂Cl₁₂, which could rank them as the top p‐type TCs discovered or predicted until now.