Organic compound passivation for perovskite solar cells with improving stability and photoelectric performance

•A novel organic compound aminophylline (APL) is found to effectively passivate the electron transport layer.•APL can not only enhance crystal grain size, but also passivate the anti-site Pb (lead) defect.•The hydrogen bond formed by ethylenediamine (in APL) and iodide ions can assist the passivation of lead defects.