Abstract Most efficient perovskite solar cells are synthesized by the one-step spin coating method. However, when applied on µm-sized textures, e.g. for efficient monolithic perovskite silicon tandems, no conformal film formation is achieved. In this respect, we investigate hybrid evaporation/ spin coating for mixed cation mixed halide perovskite absorbers [HC(NH2)2]0.83Cs0.17Pb(I1-xBrx)3 (x = 0–0.28). By control of the 2nd deposition step, we demonstrate systematic band gap tuning from 1.54 to 1.75 eV. Moreover, critical criteria for synthesis and underlying charge transport materials (CTM) are determined by investigation of planar as well as scaffolded electron transport layers. Regarding the applicability on textures, the tandem-relevant 1.7 eV high band gap absorber is deposited on planar, pyramidal, and spiky black silicon to investigate crystallization and layer formation dependent on the substrate's topography. We recommend the presented hybrid method for realization of dense crystalline perovskite films with flat surface, deposition on planar CTM, and textured Si-based tandems with random pyramids.

中文翻译：

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钙钛矿混合蒸发/旋涂方法：从带隙调整到纹理上的薄膜沉积

摘要 最高效的钙钛矿太阳能电池是通过一步旋涂法合成的。然而，当应用于微米尺寸的纹理时，例如对于高效的单片钙钛矿硅串联，无法形成保形膜。在这方面，我们研究了混合阳离子混合卤化物钙钛矿吸收剂 [HC(NH2)2]0.83Cs0.17Pb(I1-xBrx)3 (x = 0–0.28) 的混合蒸发/旋涂。通过控制第二个沉积步骤，我们展示了从 1.54 到 1.75 eV 的系统带隙调谐。此外，合成和底层电荷传输材料 (CTM) 的关键标准是通过研究平面和支架电子传输层来确定的。关于纹理的适用性，串联相关的 1.7 eV 高带隙吸收器沉积在平面、金字塔、和尖刺黑硅，以研究依赖于基板形貌的结晶和层形成。我们推荐使用所提出的混合方法来实现具有平坦表面的致密结晶钙钛矿薄膜，在平面 CTM 上沉积，以及具有随机金字塔的纹理硅基串联。