Top‐Contacts‐Interface Engineering for High‐Performance Perovskite Solar Cell With Reducing Lead Leakage
Hua̅n Bì, Gaoyi Han, Mengna Guo, Chao Ding, Shuzi Hayase, Hanjun Zou, Qing Shen, Yao Guo, Wenjing Hou
Abstract
Though great achievements have been realized in perovskite solar cells (PSCs), there are still some thorny challenges that exist such as: 1) How to minimize the interfacial nonradiative recombination losses; 2) How to balance the power conversion efficiency (PCE) and environmental friendliness of the PSCs. Here, effective top‐contacts‐interface engineering is developed via using a new multi‐active site Lewis base molecule named emtricitabine (FTC). Both, experimental and theoretical results confirm that a strong chemical interaction exists between FTC and Pb 2+ . After FTC treatment, the perovskite thin film has the lower density of defect than the control film, meanwhile, the interfacial hole extraction becomes better due to the more matched energy level. Upon the FTC passivation, the PCE of the PSCs is improved from 20.83% to 22.24%. Simultaneously, the humidity stability of the PSCs is improved after the FTC modification. Last but not least, the unpackaged target film showed less lead leakage than the control film.