Combined nanoscale strain and halide composition mapping in perovskite layers deposited on silicon for tandem solar cells.

This proposal concerns halide perovskites used as upper active layer on top of silicon for tandem solar cells. Our aim is to simultaneously map, using the ID13 nano-beam, the microstructural properties of perovskite layers, as well as the halide composition by combining XRD and XRF. The objective is to gain fundamental insights into the processes governing the microstructure of pristine and aged perovskite layers, which is of the outmost importance for further improvement of the performances of tandem cells. State-of-the-art perovskite layers deposited on flat silicon and silicon with pyramid-textured surfaces, will be studied. The influence of the deposition technique on the microstructure of pristine layers will be investigated (slot die coating vs. physical vapor deposition), as well as the effect of aging by probing slot die deposited layers exposed to controlled illumination. Finally, cross-section samples obtained by cryo-FIB will be used to probe along the layer’s depth.

本研究提案针对应用于硅基叠层太阳能电池（tandem solar cells）顶部上层活性层的卤化物钙钛矿（halide perovskites）展开研究。本研究的目标为：借助ID13纳米束线站，结合X射线衍射（X-ray Diffraction，XRD）与X射线荧光光谱（X-ray Fluorescence，XRF）技术，同时表征钙钛矿层的微观结构特性与卤化物组分分布。本研究旨在深入阐明调控原生与老化后钙钛矿层微观结构的内在机制，这对于进一步提升叠层太阳能电池的性能至关重要。本次研究将对两类先进制备的钙钛矿层展开表征：分别为沉积于平坦硅基底与金字塔纹理硅基底的钙钛矿薄膜。同时，本研究将探究沉积工艺对原生钙钛矿层微观结构的影响（对比狭缝涂布法与物理气相沉积）；此外还将通过对经受控光照老化的狭缝涂布制备钙钛矿层进行表征，分析老化过程的作用效应。最后，本研究将采用低温聚焦离子束（cryo-focused ion beam，cryo-FIB）制备的截面样品，对钙钛矿层的纵深方向进行表征分析。