The effect of utilizing a pure cis-α-dimethoxy carbonyl fulleropyrrolidine C₇₀ (DMEC₇₀) isomer as the electron transporting material (ETM) in inverted perovskite solar cells (PSCs) was evaluated. The as-prepared C₇₀ mono-adduct products are mixtures of regioisomers and the interest was to evaluate them independently as ETMs. Three different cis-DMEC₇₀ isomers (α, β-endo and β-exo) (mix-DMEC₇₀) were synthesized and purified by HPLC. It was found that PSCs based on the pure α-DMEC₇₀ exhibit a substantially enhanced maximum power conversion efficiency (PCE) of 18.6% as compared to devices based on the mixed-DMEC₇₀ isomers that yielded a PCE of 16.4%. A maximum PCE of 15.7% was observed for devices based on [6,6]-phenyl-C₇₁-butyric acid methyl ester (PC₇₁BM). This work points out the importance of using pure fullerene derivative isomers as ETMs to reduce the intrinsic energy disorder, which enhances the overall device performance.

中文翻译：

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富勒烯衍生物异构体纯度对倒置平面钙钛矿太阳能电池性能的影响

评估了在倒钙钛矿太阳能电池（PSC）中利用纯的顺式-α-二甲氧基羰基全吡咯烷C ₇₀（DMEC ₇₀）异构体作为电子传输材料（ETM）的效果。所制备的C ₇₀单加合物产物是区域异构体的混合物，有兴趣将其作为ETM进行独立评估。合成并通过HPLC纯化三种不同的顺式-DMEC ₇₀异构体（α，β-内切和β-外切）（mix-DMEC ₇₀）。结果发现基于纯是产品分成合同α-DMEC ₇₀与基于混合的DMEC ₇₀异构体的PCE产生16.4％的器件相比，其最大功率转换效率（PCE）显着提高了18.6 ％。对于基于[6,6]-苯基-C _71-丁酸甲酯（PC ₇₁ BM）的装置，观察到最大PCE为15.7％。这项工作指出了使用纯富勒烯衍生物异构体作为ETM来减少固有能量紊乱，提高整体器件性能的重要性。