The vast majority of high-performance perovskite solar cells(PSCs) are based on a formamidinium lead iodide(FAPbI_(3))-dominant composition. Nevertheless, the FA-based perovskite films suffer from undesirable phase tr...The vast majority of high-performance perovskite solar cells(PSCs) are based on a formamidinium lead iodide(FAPbI_(3))-dominant composition. Nevertheless, the FA-based perovskite films suffer from undesirable phase transition and defects-induced non-ideal interfacial recombination, which significantly induces energy loss and hinders the improvement of device performance. Herein, we employed 4-fluorophenylmethylammonium iodide(F-PMAI) to modulate surface structure and energy level alignment of the FA-based perovskite films. The superior optoelectronic films were obtained with reduced trap density, pure α-phase FAPbI_(3) and favorable energy band bending. The lifetime of photogenerated charge carriers increased from 489.3 ns to 1010.6 ns, and a more “p-type” perovskite film was obtained by the post-treatment with F-PMAI. Following this strategy, we demonstrated an improved power conversion efficiency of 22.59% for the FA-based PSCs with an open-circuit voltage loss of 399 m V.展开更多
基金funded by the National Natural Science Foundation of China(62004165)the China Postdoctoral Science Foundation(2020M670036)+2 种基金the Natural Science Foundation of Shaanxi Province,China(2020JQ195)the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(2020GXLH-Z-007,2020GXLH-Z-025)the Fundamental Research Funds for the Central Universities。
文摘The vast majority of high-performance perovskite solar cells(PSCs) are based on a formamidinium lead iodide(FAPbI_(3))-dominant composition. Nevertheless, the FA-based perovskite films suffer from undesirable phase transition and defects-induced non-ideal interfacial recombination, which significantly induces energy loss and hinders the improvement of device performance. Herein, we employed 4-fluorophenylmethylammonium iodide(F-PMAI) to modulate surface structure and energy level alignment of the FA-based perovskite films. The superior optoelectronic films were obtained with reduced trap density, pure α-phase FAPbI_(3) and favorable energy band bending. The lifetime of photogenerated charge carriers increased from 489.3 ns to 1010.6 ns, and a more “p-type” perovskite film was obtained by the post-treatment with F-PMAI. Following this strategy, we demonstrated an improved power conversion efficiency of 22.59% for the FA-based PSCs with an open-circuit voltage loss of 399 m V.
