Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, School of Materials Science and Engineering, Shandong University, Jinan, 250061, P. R. China.
Adv Mater. 2017 Nov;29(43). doi: 10.1002/adma.201703682. Epub 2017 Oct 10.
All-inorganic cesium lead halide perovskite is suggested as a promising candidate for perovskite solar cells due to its prominent thermal stability and comparable light absorption ability. Designing textured perovskite films rather than using planar-architectural perovskites can indeed optimize the optical and photoelectrical conversion performance of perovskite photovoltaics. Herein, for the first time, this study demonstrates a rational strategy for fabricating carbon quantum dot (CQD-) sensitized all-inorganic CsPbBr perovskite inverse opal (IO) films via a template-assisted, spin-coating method. CsPbBr IO introduces slow-photon effect from tunable photonic band gaps, displaying novel optical response property visible to naked eyes, while CQD inlaid among the IO frameworks not only broadens the light absorption range but also improves the charge transfer process. Applied in the perovskite solar cells, compared with planar CsPbBr , slow-photon effect of CsPbBr IO greatly enhances the light utilization, while CQD effectively facilitates the electron-hole extraction and injection process, prolongs the carrier lifetime, jointly contributing to a double-boosted power conversion efficiency (PCE) of 8.29% and an increased incident photon-to-electron conversion efficiency of up to 76.9%. The present strategy on CsPbBr IO to enhance perovskite PCE can be extended to rationally design other novel optoelectronic devices.
全无机卤化铯铅钙钛矿因其突出的热稳定性和相当的光吸收能力，被认为是钙钛矿太阳能电池的有前途的候选材料。设计具有织构的钙钛矿薄膜，而不是使用平面结构的钙钛矿，可以优化钙钛矿光伏的光学和光电转换性能。在此，本研究首次通过模板辅助的旋涂法，提出了一种合理的策略来制备碳量子点（CQD）敏化的全无机 CsPbBr 钙钛矿倒蛋白石（IO）薄膜。CsPbBr IO 从可调光子带隙引入慢光子效应，显示出肉眼可见的新型光学响应特性，而嵌入 IO 框架之间的 CQD 不仅拓宽了光吸收范围，而且提高了电荷转移过程。在钙钛矿太阳能电池中，与平面 CsPbBr 相比，CsPbBr IO 的慢光子效应大大提高了光的利用率，而 CQD 则有效地促进了电子-空穴的提取和注入过程，延长了载流子寿命，共同将功率转换效率（PCE）提高到 8.29%，并将入射光子-电子转换效率提高到 76.9%。本研究中关于 CsPbBr IO 增强钙钛矿 PCE 的策略可扩展到合理设计其他新型光电设备。
