High performance perovskite solar cells using multiple hole transport layer and modulated FAxMA1−xPbI3 active layer

Abstract

NiO layer and NiO/Ag/NiO triple layers were respectively deposited on indium-tin-oxide-coated glass substrates as the hole transport layers of MAPbI3 and FAxMA1−xPbI3 perovskite solar cells using a radio frequency magnetron sputtering system. Compared with the 60-nm-thick NiO hole transport layer with an average transmission of 66.8% between the wavelength range from 300 to 800 nm, the average transmission was improved to 70.4% for the NiO/Ag/NiO (30/7/30 nm) hole transport layer. Consequently, the power conversion efficiency of MAPbI3 perovskite solar cells using the NiO/Ag/NiO (30/7/30 nm) hole transport layer was improved from 11.02 to 11.68%. To broaden light absorption, various FAxMA1−xPbI3 active layers were obtained by blending various formamidine iodide (FAI) contents with methylammonium iodide (MAI). The power conversion efficiency of the FA0.1MA0.9PbI3 perovskite solar cells using 60-nm-thick NiO hole transport layer was improved to 12.30%. By integrating the optimal FA0.1MA0.9PbI3 active layer and the optimal NiO/Ag/NiO (30/7/30 nm) hole transport layer, the power conversion efficiency of the resulting perovskite solar cells was further improved to 12.67%.