Enhanced Thermal Stability in Perovskite Solar Cells by Assembling 2D/3D Stacking Structures

Abstract

Two-dimensional (2D) perovskites have been shown to be more stable than their three-dimensional (3D) counterparts due to the protection of the organic ligands. Herein a method is introduced to form 2D/3D stacking structures by the reaction of 3D perovskite with n-Butylamine (BA). Different from regular treatment with n-Butylammonium iodide (BAI) where 2D perovskite with various layers form, the reaction of BA with MAPbI only produce (BA)PbI, which has better protection due to more organic ligands in (BA)PbI than the mixture of 2D perovskites. Compared to BAI treatment, BA treatment results in smoother 2D perovskite layer on 3D perovskites with a better coverage. The photovoltaic devices with 2D/3D stacking structures show much improved stability in comparison to their 3D counterparts when subjected to heat stress tests. Moreover, the conversion of defective surface into 2D layers also induces passivation of the 3D perovskites resulting in an enhanced efficiency.

Ruddlesden–Popper 2D Component to Stabilize γ‐CsPbI3 Perovskite Phase for Stable and Efficient Photovoltaics

“…[32][33][34] However, the stability remains a serious issue, and researchers should pay more attention to improve CsPbI 3 black phase stability for further commercial applications. [39,40] The barrier molecules in 2D perovskite could inhibit the components decomposition, [41] phase change, [42] or oxidization, [43] when the device is exposed to ambient environment. [39,40] The barrier molecules in 2D perovskite could inhibit the components decomposition, [41] phase change, [42] or oxidization, [43] when the device is exposed to ambient environment.…”

CsPbCl3‐Driven Low‐Trap‐Density Perovskite Grain Growth for >20% Solar Cell Efficiency

“…Organic–inorganic lead halide perovskite (PVK), with its outstanding photophysical properties and versatility in low‐temperature solution processes,1, 2, 3, 4, 5, 6, 7, 8 is considered one of the most promising materials for thin‐film solar cells 9, 10, 11. In just the few years since its invention, the power conversion efficiency (PCE) of the organic–inorganic hybrid PVK solar cell (PSC) based on mixed cations and halides has been rapidly increased to as high as 22.7% 12, 13, 14…”

Enhanced Moisture Stability by Butyldimethylsulfonium Cation in Perovskite Solar Cells

“…[10] Related research [6] have shown that the small 2D crystallites formed on top of 3D MAPbI 3 layer. [11,12] The subgap quantum efficiency (QE) spectra further support the structural similarity between pristine and target perovskites (Figure 2f). In this regard, further structural analysis was performed by X-ray diffraction (XRD) analysis.…”