Gao Liguo, Zhang Fei, Chen Xihan, Xiao Chuanxiao, Larson Bryon W, Dunfield Sean P, Berry Joseph J, Zhu Kai
Chemistry and Nanoscience Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA.
Department of Chemistry, Colorado School of Mines, Golden, CO, USA.
Angew Chem Int Ed Engl. 2019 Aug 19;58(34):11737-11741. doi: 10.1002/anie.201905690. Epub 2019 Jul 11.
Organic-inorganic hybrid two-dimensional (2D) perovskites (n≤5) have recently attracted significant attention because of their promising stability and optoelectronic properties. Normally, 2D perovskites contain a monocation [e.g., methylammonium (MA ) or formamidinium (FA )]. Reported here for the first time is the fabrication of 2D perovskites (n=5) with mixed cations of MA , FA , and cesium (Cs ). The use of these triple cations leads to the formation of a smooth, compact surface morphology with larger grain size and fewer grain boundaries compared to the conventional MA-based counterpart. The resulting perovskite also exhibits longer carrier lifetime and higher conductivity in triple cation 2D perovskite solar cells (PSCs). The power conversion efficiency (PCE) of 2D PSCs with triple cations was enhanced by more than 80 % (from 7.80 to 14.23 %) compared to PSCs fabricated with a monocation. The PCE is also higher than that of PSCs based on binary cation (MA -FA or MA -Cs ) 2D structures.
有机-无机杂化二维（2D）钙钛矿（n≤5）由于其有望具备的稳定性和光电特性，近来受到了广泛关注。通常，二维钙钛矿包含一种单阳离子[例如，甲胺（MA ）或甲脒（FA ）]。本文首次报道了含有MA 、FA 和铯（Cs ）混合阳离子的二维钙钛矿（n=5）的制备。与传统的基于MA 的对应物相比，这些三阳离子的使用导致形成了具有更大晶粒尺寸和更少晶界的光滑、致密的表面形态。所得钙钛矿在三阳离子二维钙钛矿太阳能电池（PSC）中还表现出更长的载流子寿命和更高的电导率。与用单阳离子制造的PSC相比，具有三阳离子的二维PSC的功率转换效率（PCE）提高了80%以上（从7.80%提高到14.23%）。该PCE也高于基于二元阳离子（MA -FA 或MA -Cs ）二维结构的PSC。
