Graded Bandgap CsPbI2+xBr1-x Perovskite Solar Cells with a Stabilized Efficiency of 14.4%
Graded Bandgap CsPbI2+xBr1-x Perovskite Solar Cells with a Stabilized Efficiency of 14.4%
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分级%20带隙%20CsPbI2+Br1～%20钙钛矿%20Solar%20Cells%20with%20a%20Stabilized%20Efficiency%20of%2014.4%
DOI：
10.1016/j.joule.2018.04.012
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发表时间：
2018-08-15
期刊：
影响因子：
39.8
通讯作者：
Liu, Shengzhong (Frank)
中科院分区：
文献类型：
--
作者：
Bian, Hui;Bai, Dongliang;Liu, Shengzhong (Frank)
全无机钙钛矿由于其优异的太阳能电池性能和大气稳定性而在光伏应用中显示出巨大的潜力。在这里，使用 CsPbBrI2 和 CsPbI3 量子点作为组件电池探索了具有分级带隙的 CsPbI2+xBr1-x 钙钛矿太阳能电池。采取了四种策略来提高设备性能。首先，制备CsPbI2Br薄膜作为主要吸收体，组件电池表现出高达13.45%的惊人功率转换效率（PCE）。其次，通过Mn2+取代、SCN-封端和[(NH2)(2)CH](+)处理，获得了稳定且高迁移率的CsPbI3量子点(QD)薄膜。第三，在 CsPbBrI2/CsPbI3 QD 界面处设计了卤化物离子异质结，以实现适当的带边缘弯曲作为分级带隙，从而改善载流子收集。最后，CsPbI3 QD 层在分级带隙结构中进行了优化，以实现最大的整体光捕获。结果，该器件的 PCE 为 14.45%。这是迄今为止无机钙钛矿太阳能电池报道的最高效率。
All-inorganic perovskite shows great potential for photovoltaic applications due to its excellent solar cell performance and atmospheric stability. Here, a CsPbI2+xBr1-x perovskite solar cell with a graded bandgap is explored using CsPbBrI2 and CsPbI3 quantum dots as component cells. Four strategies were pursued to boost the device performance. First, CsPbI2Br film was fabricated as the main absorber, with the component cell showing remarkable power conversion efficiency (PCE) as high as 13.45%. Second, by Mn2+ substitution, SCN- capping, and [(NH2)(2)CH](+) treatment, stable and high-mobility CsPbI3 quantum dot (QD) film was attained. Third, a halide-ion-profiled heterojunction was designed at the CsPbBrI2/CsPbI3 QD interface to achieve proper band-edge bending as graded bandgap for improved carrier collection. Finally, the CsPbI3 QD layer was optimized in the graded bandgap structure to achieve maximum overall light harvesting. As a result, the device achieved a PCE of 14.45%. This is the highest efficiency ever reported for inorganic perovskite solar cells.