TY  - EJOU
AU  - Zhang, Qixian 
AU  - Guo, Yi 
AU  - Liu, Huicong 
AU  - Li, Weiping 
AU  - Zhu, Liqun 
AU  - Chen, Haining 

TI  - Treating CsPbI<sub>3</sub> Perovskite with Pyrrolidinium Iodide to Improve the Performance of Perovskite Solar Cells
T2  - Journal of Renewable Materials

PY  - 2023
VL  - 11
IS  - 8
SN  - 2164-6341

AB  - All-inorganic CsPbI<sub>3</sub> perovskite has attracted wide attention due to its desirable optical bandgap (<i>E<sub>g</sub></i>: ∼1.7 eV) as
well as high chemical stability. Nevertheless, the photovoltaic performance of CsPbI<sub>3</sub> perovskite solar cells (PSCs)
was limited by severe nonradiative charge recombination due to high defect density at the grain boundary and
surface of perovskite films. To address this issue, a pyrrolidinium iodide (PyI) molecule was introduced to modify
the surface and grain boundary of CsPbI<sub>3</sub> perovskite films to passivate defects, which improves the quality of
CsPbI<sub>3</sub> perovskite films as well as induces the generation of a quasi-2D Py<sub>2</sub>CsPb<sub>2</sub>I<sub>7</sub> capping layer between perovskite layer and hole transport layer. Such quasi-2D Py<sub>2</sub>CsPb<sub>2</sub>I<sub>7</sub> capping layer optimizes interface contact
between CsPbI<sub>3</sub> perovskite layer and hole transport layer and blocks the electron transfer from CsPbI<sub>3</sub> perovskite
photoactive layer to the hole transport layer. As a result, the performance of CsPbI<sub>3</sub> PSCs is well improved to
17.87% for power conversion efficiency (PCE) with an ultra-high fill factor (FF) of 0.84. In addition, the PyI molecule modified CsPbI<sub>3</sub> perovskite devices exhibit excellent stability, which remains its initial PCE almost
unchanged after aging for 35 days under the dry air atmosphere (temperature: 20°C–30°C, control relative humidity (RH): <10%).
KW  - CsPbI<sub>3</sub>; inorganic; perovskite; defect passivation; pyrrolidinium iodide

DO  - 10.32604/jrm.2023.027730