Zhang Cuiling, Liu Chong, Gao Yanyan, Zhu Shusheng, Chen Fang, Huang Boyuan, Xie Yi, Liu Yaqing, Ma Mengen, Wang Zhen, Wu Shaohang, Schropp Ruud E I, Mai Yaohua
Institute of New Energy Technology, College of Information Science and Technology, Guangdong Engineering Research Center of Thin-Film Photovoltaic Processes and Equipment, and Key Laboratory of New Semiconductors and Devices of Guangdong Higher Education Institutes, Jinan University, Guangzhou, 510632, China.
Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China.
Adv Sci (Weinh). 2022 Nov;9(33):e2204138. doi: 10.1002/advs.202204138. Epub 2022 Oct 17.
Indoor photovoltaics (IPVs) are expected to power the Internet of Things ecosystem, which is attracting ever-increasing attention as part of the rapidly developing distributed communications and electronics technology. The power conversion efficiency of IPVs strongly depends on the match between typical indoor light spectra and the band gap of the light absorbing layer. Therefore, band-gap tunable materials, such as metal-halide perovskites, are specifically promising candidates for approaching the indoor illumination efficiency limit of ∼56%. However, perovskite materials with ideal band gap for indoor application generally contain high bromine (Br) contents, causing inferior open-circuit voltage (V ). By fabricating a series of wide-bandgap perovskites (Cs FA PbI Br , 0.6 ≤ x ≤ 1.6) with varying Br contents and related band gaps, it is found that, the high Br vacancy (V ) defect density is a significant reason that leading to large V deficits apart from the well-accepted halide segregation. The introduction of I-rich alkali metal small-molecule compounds is demonstrated to suppress the V and increase the V of perovskite IPVs up to 1.05 V under 1000 lux light-emitting diode illumination, one of the highest V values reported so far. More importantly, the modules are sent for independent certification and have gained a record efficiency of 36.36%.
室内光伏（IPV）有望为物联网生态系统供电，作为快速发展的分布式通信和电子技术的一部分，该生态系统正吸引着越来越多的关注。IPV的功率转换效率在很大程度上取决于典型室内光谱与光吸收层带隙之间的匹配。因此，诸如金属卤化物钙钛矿之类的带隙可调材料是接近约56%的室内照明效率极限的特别有前景的候选材料。然而，具有适合室内应用的理想带隙的钙钛矿材料通常含有高溴（Br）含量，导致开路电压（V）较低。通过制备一系列具有不同Br含量和相关带隙的宽带隙钙钛矿（CsFA PbIₓBr₃₋ₓ，0.6≤x≤1.6），发现除了公认的卤化物偏析外，高Br空位（VBr）缺陷密度是导致大V亏缺的一个重要原因。在1000勒克斯发光二极管照明下，富碘碱金属小分子化合物的引入被证明可以抑制V亏缺，并将钙钛矿IPV的V值提高到1.05 V，这是迄今为止报道的最高V值之一。更重要的是，这些模块已送去进行独立认证，并获得了36.36%的创纪录效率。
