Efficient and Stable All-Inorganic Niobium-Incorporated CsPbI₂Br-Based Perovskite Solar Cells

Abstract

Inorganic cesium lead halide perovskite (CsPbX 3 ) is a promising lightharvesting material to increase the thermal stability and the device performance as compared to the organic−inorganic hybrid counterparts. However, the photoactive stability at ambient conditions is an unresolved issue. Here, we studied the influence of Nb 5+ ions' incorporation in the CsPbI 2 Br perovskite processed at ambient conditions. Our results exhibited that 0.5% Nb-incorporated CsPb 1−x Nb x I 2 Br (herein x = 0.005) thin films show excellent uniformity and improved grain size because of the optimum concentration of Nb 5+ doping and hot-air flow. The improved grain size and uniform film thickness deliver a superior interface between the CsPb 1−x Nb x I 2 Br layer and the hole-transporting material. The fabricated all-inorganic perovskite solar cell (IPVSC) devices exhibited the Nb 5+ cation incorporation which enables decreased charge recombination, leading to negligible hysteresis. The champion device produces an open-circuit voltage (V OC ) as high as 1.317 V. The IPVSC device containing a CsPb 0.995 Nb 0.005 I 2 Br composition delivers the highest power conversion efficiency of 16.45% under a 100 mW cm −2 illumination and exhibits a negligible efficiency loss over 96 h in ambient conditions.

Quantifying Efficiency Limitations in All‐Inorganic Halide Perovskite Solar Cells

“…b) The distribution of g ip E for all-inorganic perovskites. The data points are collected from relevant publications of CsPbI 3 , [25,26,[36][37][38][39][40][41] CsPbI 2 Br, [29,[42][43][44][45][46][47][48][49][50][51] CsPbIBr 2 , [30,[52][53][54][55][56][57] CsPbBr 3 , [58][59][60][61][62] of which detailed data can be found in Tables 1-5.…”

Study on the Ion Substitution Mechanism of CsPbIBr2 Films Prepared by a Drop-Coating Method

“…FromFigure a, the EIS measurement was performed at an applied bias of 0.8 V in the dark environment. The equivalent circuit (EC) diagram was shown in the inset of Nyquist plots. , The fitting results are shown in Table S7. Compared with the devices fabricated without methanol solution (58.6 and 3743.4 Ω), the devices fabricated with 30 μL of CsBr methanol solution showed an increased R s of 65.5 Ω and a decreased R ct of 2559.8 Ω, while the devices fabricated with 90 μL of CsI methanol solution showed a decreased R s of 43.2 Ω and an increased R ct of 4554.9 Ω.…”

All‐Inorganic CsPbI2Br Perovskite Solar Cells: Recent Developments and Challenges

“…For instance, the Zn + cation can effectively improve the grain size and control the crystal growth of the CsPbI 2 Br film due to its stronger interaction with halide ions. [ 244 ] Yin and Patil et al [ 245 ] reported the positive influence of B‐site doping of Nb 5+ in improving the PV performance of CsPbI 2 Br. It was suggested that the 0.5% Nb‐incorporated perovskite film exhibited enlarged grain size and remarkable uniformity, delivering a superior interface between the HTL and the perovskite layer.…”