Caporali Stefano, Martinuzzi Stefano Mauro, Gabellini Lapo, Calisi Nicola
Department of Industrial Engineering (DIEF), University of Florence, Via di Santa Marta n. 3, 50139 Florence, Italy.
National Interuniversity Consortium of Materials Science and Technology (INSTM), Florence Research Unit, Via G. Giusti n. 9, 50121 Florence, Italy.
Materials (Basel). 2023 Jul 27;16(15):5276. doi: 10.3390/ma16155276.
Nontoxic all-inorganic perovskites are among the most promising materials for the realization of optoelectronic devices. Here, we present an innovative way to deposit lead-free, totally inorganic CsBiI perovskite from vapor phase. Taking use of a magnetron sputtering system equipped with a radiofrequency working mode power supply and a single target containing the correct ratio of CsI and BiI salts, it was possible to deposit a CsBiI perovskitic film on silicon and soda-lime glass. The target composition was optimized to obtain a stoichiometric deposition, and the best compromise was found with a mix enriched with 20% / of CsI. Secondly, the effect of post-deposition thermal treatments (150 °C and 300 °C) and of the deposition on a preheat substrate (150 °C) were evaluated by analyzing the chemical composition, the morphology, the crystal structure, and the optical properties. The thermal treatment at 150 °C improved the uniformity of the perovskite film; the one at 300 °C damaged the perovskite deposited. Depositing on a preheated substrate at 150 °C, the obtained film showed a higher crystallinity. An additional thermal treatment at 150 °C on the film deposed on the preheated substrate showed that the crystallinity remains high, and the morphology becomes more uniform.
无毒全无机钙钛矿是实现光电器件最有前途的材料之一。在此，我们提出一种从气相沉积无铅、完全无机CsBiI钙钛矿的创新方法。利用配备射频工作模式电源的磁控溅射系统和含有正确比例CsI和BiI盐的单一靶材，能够在硅和钠钙玻璃上沉积CsBiI钙钛矿薄膜。对靶材成分进行了优化以实现化学计量沉积，发现富含20% CsI的混合物是最佳折衷方案。其次，通过分析化学成分、形貌、晶体结构和光学性质，评估了沉积后热处理（150℃和300℃）以及在预热衬底（150℃）上沉积的效果。150℃的热处理提高了钙钛矿薄膜的均匀性；300℃的热处理损坏了沉积的钙钛矿。在150℃的预热衬底上沉积时，所得薄膜显示出更高的结晶度。对在预热衬底上沉积的薄膜进行150℃的额外热处理表明，结晶度仍然很高，形貌变得更加均匀。
