Mesoporous-Carbon-Based Fully-Printable All-Inorganic Monoclinic CsPbBr<sub>3</sub> Perovskite Solar Cells with Ultrastability under High Temperature and High Humidity
Shiyu Wang, Wenjian Shen, Yanmeng Chu, Weihua Zhang, Hong Li, Anyi Mei, Yaoguang Rong, Yiwen Tang, Yue Hu, Hongwei Han
Abstract
The all-inorganic CsPb(IxBr1–x)3 (0 ≤ x ≤ 1) perovskite solar cells (PSCs) are attractive by virtue of their high environmental and thermal stability. Nevertheless, multiple-step deposition and high annealing temperature (>250 °C) and the structural and optoelectronic properties changes upon temperature-dependent phase-transition are potential impediments for highly efficient and stable PSCs. Herein, a space-confined method to fabricate stable lower-order symmetric pure monoclinic CsPbBr3 phase at low temperature (<50 °C) is for the first time reported. It is found that the carbon-based mesoporous fully printable area can inhibit the phase transition to get a pure phase. Therefore, the device exhibits a power conversion efficiency of 7.52% with a low hysteresis index of 0.024. Moreover, the device passed the 1000 h 85 °C thermal test and the 200 cycles thermal cycling test according to IEC-61625 stability tests. These are critical progresses for achieving long-term stability and the stable pure inorganic perovskite phase of high-performance photovoltaics.