Ni-Doped SnO(2) as an Electron Transport Layer by a Low-Temperature Process in Planar Perovskite Solar Cells

[Image: see text] Perovskite solar cells (PSCs) based on a planar structure have recently become more attractive due to their simple manufacturing process and relatively low cost, while most perovskite solar cells employ highly porous TiO(2) as an electron transport layer in mesoporous devices offering higher energy conversion efficiency (PCE). In planar structural devices, non-radiative recombination effects of the absorber layer and the electron transport layer cause potential loss and lower PCE. We created an efficient electron transport layer by combining low-temperature Ni-doped SnO(2) with SDBS as a surfactant (denoted as Ni:SnO(2)). Doping Ni(+) into low-temperature solution-processed SnO(2) increased the power conversion efficiency of PSCs from 17.8 to 19.7%.