Liu Guozhen, Zheng Haiying, Zhu Liangzheng, Alsaedi Ahmed, Hayat Tasawar, Pan Xu, Mo Li'e, Dai Songyuan
Key Laboratory of Photovoltaic and Energy Conservation Materials, Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, PR China.
University of Science and Technology of China, Hefei, 230026, PR China.
ChemSusChem. 2018 Jul 20;11(14):2436-2443. doi: 10.1002/cssc.201800658. Epub 2018 Jul 3.
Although the power conversion efficiency (PCE) of perovskite solar cells (PSCs) has increased to 22.7 %, the instability when exposed to moisture and heat has hindered their further practical development. In this study, to gain highly efficient and stable perovskite components, methylammonium (MA), Cs, and Rb cations are introduced into a (FAPbI ) (FAPbBr ) (FA=formamidine) film, which is rarely used because of its poor photovoltaic performance. The effects of different contents of MA, Cs, or Rb cations on the performance of (FAPbI ) (FAPbBr ) films and devices are systematically studied. The results show that the devices with Cs cations exhibit markedly improved photovoltaic performance and stability, attributed to the clearly enhanced quality of films and their intrinsic stability. The (FAPbI ) (FAPbBr ) devices with 10 % Cs show a PCE as high as 19.94 %. More importantly, the unsealed devices retain about 80 % and 90 % of the initial PCE at 85 °C after 260 h and under 45±5 % relative humidity (RH) after 1440 h, respectively, which are better than that with 15 % MA and 5 % Rb under the same conditions. This indicates that a highly efficient and stable perovskite component has been achieved, and PSCs based on this component are expected to promote their further development.
尽管钙钛矿太阳能电池（PSCs）的功率转换效率（PCE）已提高到22.7%，但其在暴露于湿气和热时的不稳定性阻碍了它们的进一步实际发展。在本研究中，为了获得高效且稳定的钙钛矿组件，将甲铵（MA）、铯（Cs）和铷（Rb）阳离子引入到（FAPbI ）（FAPbBr ）（FA = 甲脒）薄膜中，该薄膜因其较差的光伏性能而很少被使用。系统地研究了不同含量的MA、Cs或Rb阳离子对（FAPbI ）（FAPbBr ）薄膜及器件性能的影响。结果表明，含有Cs阳离子的器件表现出显著改善的光伏性能和稳定性，这归因于薄膜质量的明显提高及其固有稳定性。含有10% Cs的（FAPbI ）（FAPbBr ）器件的PCE高达19.94%。更重要的是，未封装的器件在85°C下260小时后以及在45±5%相对湿度（RH）下1440小时后，分别保留了初始PCE的约80%和90%，这比在相同条件下含有15% MA和5% Rb的器件要好。这表明已实现了一种高效且稳定的钙钛矿组件，基于该组件的PSCs有望推动其进一步发展。
