Li Zhenxing, Wang Ping, Ma Chang, Igbari Femi, Kang Yikun, Wang Kai-Li, Song Weiyu, Dong Chong, Li Yanjie, Yao Jiasai, Meng Dong, Wang Zhao-Kui, Yang Yang
State Key Laboratory of Heavy Oil Processing, College of New Energy and Materials, China University of Petroleum (Beijing), Beijing 102249, China.
BTR New Energy Materials Inc., Bao'an District, Shenzhen 518106, China.
J Am Chem Soc. 2021 Feb 17;143(6):2593-2600. doi: 10.1021/jacs.0c12739. Epub 2021 Feb 3.
The inorganic lead-free CsAgBiBr double perovskite structure is the promising development direction in perovskite solar cells (PSCs) to solve the problem of the instability of the APbX structure and lead toxicity. However, the low short-circuit current and power conversion efficiency (PCE) caused by the low crystallization of CsAgBiBr greatly limit the optoelectronic application. Herein, we adopt a simple strategy to dope single-layered MXene nanosheets into titania (TiCT@TiO) as a multifunctional electron transport layer for stable and efficient CsAgBiBr double PSCs. The single-layered MXene nanosheets significantly improve the electrical conductivity and electron extraction rate of TiO; meanwhile, the single-layered MXene nanosheets change the surface wettability of the electron transport layer and promote the crystallization of the CsAgBiBr double perovskite in solar cell devices. Therefore, the PCE went up by more than 40% to 2.81% compared to that of a TiO based device, and the hysteresis was greatly suppressed. Furthermore, the device based on TiCT@TiO showed the long-term operating stability. After storing the device for 15 days under ambient air conditions, the PCE still remained a retention rate of 93% of the initial one. Our finding demonstrates the potential of TiCT@TiO in electron transfer material of high-performance double PSCs.
无机无铅CsAgBiBr双钙钛矿结构是钙钛矿太阳能电池（PSC）中解决APbX结构不稳定性和铅毒性问题的有前景的发展方向。然而，CsAgBiBr结晶度低导致的短路电流和功率转换效率（PCE）低极大地限制了其光电应用。在此，我们采用一种简单策略，将单层MXene纳米片掺杂到二氧化钛（TiCT@TiO）中作为多功能电子传输层，用于稳定高效的CsAgBiBr双钙钛矿太阳能电池。单层MXene纳米片显著提高了TiO的电导率和电子提取率；同时，单层MXene纳米片改变了电子传输层的表面润湿性，并促进了太阳能电池器件中CsAgBiBr双钙钛矿的结晶。因此，与基于TiO的器件相比，PCE提高了40%以上，达到2.81%，并且滞后现象得到了极大抑制。此外，基于TiCT@TiO的器件表现出长期运行稳定性。在环境空气条件下将器件储存15天后，PCE仍保持初始值的93%的保留率。我们的发现证明了TiCT@TiO在高性能双钙钛矿太阳能电池电子传输材料中的潜力。
