全无机钙钛矿电池规避了传统钙钛矿电池中有机材料易吸湿、易分解的问题，因而具有良好的水汽、光照、热稳定性，但目前瓶颈是带隙较大（>1.8eV），能量损失严重，不适于单结或叠层电池活性层；CsPbI3钙钛矿的带隙为1.73eV，基于该材料的光伏器件有望作为叠层电池顶电池使用，与硅叠层，应用前景好，但因其钙钛矿相难以稳定，实际应用受到限制。本项目基于申请人从博士阶段即关注的钙钛矿稳定性问题，结合工作单位课题组在薄膜电池和无机材料方面的前期基础，开展全无机CsPbI3钙钛矿电池研究。以减小结构畸变和降低晶体维度为指导，理性调控CsPbI3的组成与结构，提高其结构稳定性；研究外来离子对结构畸变和维度（三维--->准二维--->二维）的调控作用，及其对带隙、电荷输运、缺陷浓度等的影响，揭示结构畸变、晶体维度与光电性质、光伏性能的构效关系；采用无机电子和空穴传输层制备高效、稳定的全无机钙钛矿太阳能电池。

All inorganic perovskite solar cells avoid the risks of hygroscopicity and decomposition for organic-inorganic hybrid perovskites, and thereby exhibit excellent stability toward moisture, light soaking, and thermal treatment. However, most of the inorganic perovskites are not suitable for single junction or tandem solar cells due to their large band gaps (> 1.8 eV) and thus serious loss in light absorption. Fortunately, CsPbI3 perovskite, with a band gap of 1.73 eV, could potentially serve as top cells in tandem devices with silicon solar cells. The current restriction for CsPbI3 is the poor perovskite phase stability, limiting their performance when phase changing to yellow δ-CsPbI3. This project aims to stabilize CsPbI3 perovskite phase as well as maintaining the band gap characters, under the guidance of lowering structure distortion and decreasing crystal dimensionality through introduction of foreign ions. In addition, we will mainly focus on the deep mechanism of structure distortion and dimensionality control by foreign ions, the influence of structure on optical and electronic properties, such as band gap, carrier transport, and defect concentration et al. Finally, this project will also develop inorganic electron and hole transport materials, aiming to fabricate all-inorganic perovskite solar cells with high performance and long-term stability.