Choi Yong Chan, Hwang Eunjeong
Division of Energy Technology, DGIST, Daegu 42988, Korea.
Nanomaterials (Basel). 2019 Nov 20;9(12):1650. doi: 10.3390/nano9121650.
Pb-based hybrid perovskite solar cells, despite their advantages, face challenges in commercialization. In recent years, Bi-based chalcohalides are being considered as potential alternative candidates, however, their current device efficiency remains unsatisfactory. Herein, a two-step solution method is developed and applied to the fabrication of BiSI films. The method consists of the formation of BiS (step I) and its conversion to BiSI (step II). The BiS was fabricated by a thiol-amine solution process and the BiSI conversion was achieved by chemical reaction between the as-formed BiS and BiI. It was found that the formation of BiSI was highly dependent on the Bi:S molar ratio of the BiO-thiourea solution and the number of times of step I. The as-fabricated BiSI film had an optical band gap of 1.61 eV and exhibited nanorod morphology. In addition, the electronic structure is explored and discussed for solar cells applications.
基于铅的混合钙钛矿太阳能电池尽管具有优势，但在商业化方面面临挑战。近年来，基于铋的卤硫族化合物正被视为潜在的替代候选材料，然而，其当前器件效率仍不尽人意。在此，开发了一种两步溶液法并将其应用于制备BiSI薄膜。该方法包括BiS的形成（步骤I）及其转化为BiSI（步骤II）。BiS通过硫醇 - 胺溶液工艺制备，BiSI转化通过所形成的BiS与BiI之间的化学反应实现。发现BiSI的形成高度依赖于BiO - 硫脲溶液的Bi:S摩尔比以及步骤I的次数。所制备的BiSI薄膜具有1.61 eV的光学带隙并呈现纳米棒形态。此外，还针对太阳能电池应用对其电子结构进行了探索和讨论。
