Xu Xiao-Li, Xiao Ling-Bo, Zhao Jie, Pan Bing-Kun, Li Jun, Liao Wei-Qiang, Xiong Ren-Gen, Zou Gui-Fu
College of Energy, Soochow Institute for Energy and Materials InnovationS, Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou, 215006, China.
Ordered Matter Science Research Center, Nanchang University, Nanchang, 330031, P. R. China.
Angew Chem Int Ed Engl. 2020 Nov 2;59(45):19974-19982. doi: 10.1002/anie.202008494. Epub 2020 Sep 8.
The nonradiative recombination of electrons and holes has been identified as the main cause of energy loss in hybrid organic-inorganic perovskite solar cells (PSCs). Sufficient built-in field and defect passivation can facilitate effective separation of electron-hole pairs to address the crucial issues. For the first time, we introduce a homochiral molecular ferroelectric into a PSC to enlarge the built-in electric field of the perovskite film, thereby facilitating effective charge separation and transportation. As a consequence of similarities in ionic structure, the molecular ferroelectric component of the PSC passivates the defects in the active perovskite layers, thereby inducing an approximately eightfold enhancement in photoluminescence intensity and reducing electron trap-state density. The photovoltaic molecular ferroelectric PSCs achieve a power conversion efficiency as high as 21.78 %.
电子与空穴的非辐射复合已被确定为有机-无机杂化钙钛矿太阳能电池（PSC）能量损失的主要原因。足够的内建电场和缺陷钝化有助于电子-空穴对的有效分离，从而解决关键问题。我们首次将一种纯手性分子铁电体引入PSC中，以扩大钙钛矿薄膜的内建电场，从而促进电荷的有效分离和传输。由于离子结构相似，PSC的分子铁电组分钝化了活性钙钛矿层中的缺陷，从而使光致发光强度提高了约八倍，并降低了电子陷阱态密度。光伏分子铁电PSC实现了高达21.78%的功率转换效率。
