High performance, hysteresis-free, low temperature n-i-p perovskite solar cells are successfully fabricated by solution processing using fullerene electron transport layer (ETL). PC₇₁BM fullerene, with broader absorption spectrum and lower HOMO level, when incorporated in the perovskite solar cell yielded average power conversion efficiency (PCE) of 13.9%. This is the highest reported PCE in n-i-p perovskite solar cells with PC₇₁BM ETL. The devices exhibited negligible hysteresis and high open-circuit voltage (V_oc). On the contrary, devices with PC₆₁BM, a common fullerene ETL in perovskite solar cell, exhibited large hysteresis and lower V_oc. The underlying mechanisms of superior performance of devices with PC₇₁BM ETL were found to be correlated with fullerene surface wettability and perovskite grain size. The influence of fullerene ETL on the perovskite grain growth and subsequent photovoltaic performance was investigated by contact angle measurement, morphological characterization of the surface topography and electrochemical impedance analysis.

通过使用富勒烯电子传输层（ETL）进行溶液处理，成功制造了高性能，无滞后，低温压合钙钛矿太阳能电池。当掺入钙钛矿太阳能电池中时，具有更宽的吸收光谱和更低的HOMO含量的PC ₇₁ BM富勒烯的平均功率转换效率（PCE）为13.9％。这是在采用PC ₇₁ BM ETL的钙钛矿型太阳能电池中报道最多的PCE 。这些器件的磁滞可忽略不计，并且开路电压（V _oc）高。相反，具有钙钛矿型太阳能电池中常见的富勒烯ETL PC ₆₁ BM的器件表现出较大的磁滞现象和较低的V _oc。发现具有PC ₇₁ BM ETL的设备卓越性能的根本机理与富勒烯表面润湿性和钙钛矿晶粒尺寸有关。通过接触角测量，表面形貌的形态表征和电化学阻抗分析，研究了富勒烯ETL对钙钛矿晶粒生长和随后的光伏性能的影响。