Li Shuo, Zai Shuwan, Wei Xingpei, Yang Fei, Huang Wenliang, Yuan Ningyi, Ding Jianning, Zhao Kui, Liu Shengzhong Frank, Zhao Wangen
Key Laboratory for Applied Surface and Colloid Chemistry, National Ministry of Education, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710062, P. R. China.
Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Province Cultivation Base for State Key Laboratory of Photovoltaic Science and Technology, School of Materials Science and Engineering, Changzhou University, Changzhou, 213164, P. R. China.
Small. 2024 Dec;20(50):e2406960. doi: 10.1002/smll.202406960. Epub 2024 Sep 23.
High-quality CsPbI with low defect density is indispensable for acquiring excellent photoelectric performance. Meticulous regulation of the CsPbI crystal growth processes is both feasible and efficacious in enhancing the quality of perovskite films. In this study, the cesium formate (CsFo) is introduced. On one hand, its low melting point can induce the crystallization processes at a low level of energy consumption. On the other hand, the pseudo-halide anion can participate in the passivation of iodide vacancies, as the formate anion exhibits a relatively higher affinity with iodide vacancies compared to other halides. Consequently, the introduction of CsFo enhances the quality of CsPbI thin films by altering the crystallization process and curbing defect formation. As a result, a steady-state output efficiency of 21.23% and an open-circuit voltage (V) as high as 1.25 V are achieved, with both parameters ranking among the highest for this type of solar cell.
具有低缺陷密度的高质量CsPbI对于获得优异的光电性能必不可少。对CsPbI晶体生长过程进行精细调控，在提高钙钛矿薄膜质量方面既可行又有效。在本研究中，引入了甲酸铯（CsFo）。一方面，其低熔点可在低能耗水平下诱导结晶过程。另一方面，伪卤化物阴离子可参与碘空位的钝化，因为与其他卤化物相比，甲酸根阴离子与碘空位表现出相对更高的亲和力。因此，CsFo的引入通过改变结晶过程和抑制缺陷形成来提高CsPbI薄膜的质量。结果，实现了21.23%的稳态输出效率和高达1.25 V的开路电压（V），这两个参数在此类太阳能电池中均名列前茅。
