Department of Materials Science and Engineering, University of Washington, Seattle, WA, 98195-2120, USA.
Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China.
Adv Mater. 2017 Dec;29(47). doi: 10.1002/adma.201703980. Epub 2017 Nov 13.
Employing a layer of bulk-heterojunction (BHJ) organic semiconductors on top of perovskite to further extend its photoresponse is considered as a simple and promising way to enhance the efficiency of perovskite-based solar cells, instead of using tandem devices or near infrared (NIR)-absorbing Sn-containing perovskites. However, the progress made from this approach is quite limited because very few such hybrid solar cells can simultaneously show high short-circuit current (J ) and fill factor (FF). To find an appropriate NIR-absorbing BHJ is essential for highly efficient, organic, photovoltaics (OPV)/perovskite hybrid solar cells. The materials involved in the BHJ layer not only need to have broad photoresponse to increase J , but also possess suitable energy levels and high mobility to afford high V and FF. In this work, a new porphyrin is synthesized and blended with [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) to function as an efficient BHJ for OPV/perovskite hybrid solar cells. The extended photoresponse, well-matched energy levels, and high hole mobility from optimized BHJ morphology afford a very high power conversion efficiency (PCE) (19.02%) with high V , J , and FF achieved simultaneously. This is the highest value reported so far for such hybrid devices, which demonstrates the feasibility of further improving the efficiency of perovskite devices.
在钙钛矿的顶部采用体异质结 (BHJ) 有机半导体进一步扩展其光响应被认为是提高基于钙钛矿的太阳能电池效率的一种简单而有前途的方法，而不是使用串联器件或近红外 (NIR) 吸收含锡的钙钛矿。然而，这种方法的进展非常有限，因为很少有这种混合太阳能电池能够同时显示出高短路电流 (J) 和填充因子 (FF)。找到合适的 NIR 吸收 BHJ 对于高效的有机光伏 (OPV)/钙钛矿混合太阳能电池至关重要。BHJ 层中涉及的材料不仅需要具有宽光响应以增加 J，还需要具有合适的能级和高迁移率以提供高 V 和 FF。在这项工作中，合成了一种新的卟啉，并与 [6,6]-苯基-C61-丁酸甲酯 (PCBM) 混合作为高效的 OPV/钙钛矿混合太阳能电池的 BHJ。优化的 BHJ 形态提供了扩展的光响应、匹配良好的能级和高空穴迁移率，从而实现了非常高的功率转换效率 (PCE) (19.02%)，同时实现了高 V、J 和 FF。这是迄今为止此类混合器件的最高值，证明了进一步提高钙钛矿器件效率的可行性。
