Abstract:

Inorganic perovskites have attracted a lot of attention due to their excellent optical and thermal stability, but high-efficiency inorganic perovskite solar cells often need to be modified with organic materials, which limits the improvement of device stability to a certain extent. In order to effectively solve this problem, a phase heterojunction (PHJ) strategy was proposed to modify interface inorganic perovskite solar cells (IPSCs) with high efficiency. The PHJ was constructed between the upper interface of the optical absorption layer and the hole transport layer of the inorganic perovskite by spinning methanol solution and evaporating cesium iodide (CsI). Effective management of interface defects is achieved, non-radiative recombination is reduced, and carrier driving and separation are facilitated. Finally, N-I-P IPSCs based on the PHJ strategy achieved a photoelectric conversion efficiency of 20.56%, much higher than the 18.03% of the reference group, and retained 86.14% of their initial efficiency when placed in 65℃ nitrogen (N₂) atmosphere for 1000 h.

Key words: inorganic perovskites, solar energy, stability, interface, phase heterojunction, non-radiative recombination

摘要：

无机钙钛矿因其优异的光、热稳定性而备受关注，但往往高效率的无机钙钛矿太阳能电池要用到有机材料进行修饰，在一定程度上限制了器件稳定性的提升。为了有效解决这一问题，提出一种相异质结（PHJ）策略用以界面修饰制备高效率的无机钙钛矿太阳能电池（IPSCs），即在无机钙钛矿的光吸收层上界面和空穴传输层之间利用旋涂甲醇溶液结合蒸发碘化铯（CsI）的方式进行PHJ的构建。实现了界面缺陷的有效管理，降低了非辐射复合，促进了载流子的驱动和分离。最终，基于该PHJ策略的正式结构（N-I-P型）IPSCs实现了20.56%的光电转换效率，远高于参考组的18.03%，在65℃的氮气（N₂）氛围下放置1000 h，可保留其初始效率的86.14%。

关键词: 无机钙钛矿, 太阳能, 稳定性, 界面, 相异质结, 非辐射复合