First-principles insights of electronic and optical properties of Zn-doped CH3NH3PbI3 for photovoltaic applications

Using density functional theory calculations, we investigated the structural stability, electronic and optical properties of Zn-doped MAPbI(3). The results indicate that Zn-doped hybrid perovskites are unstable compared with MAPbI(3). The instability and band gap of Zn-doped MAPbI(3) gradually increase when the proportion of Zn increases. Interestingly, the results show that the optical absorption of MAPb(0.96875)Zn(0.03125)I(3) is stronger than that of MAPbI(3). Moreover, MAPb(0)(.)(96875)Zn(0.03125)I(3) possesses small formation energy and a suitable band gap, which is predicted to possess better photovoltaic performance. This work provides a feasible way to reduce the amount of Pb and improve photovoltaic performance of perovskite solar cells. (C) 2019 The Japan Society of Applied Physics