van Embden Joel, Della Gaspera Enrico
School of Science , RMIT University , Melbourne , Victoria 3000 , Australia.
ACS Appl Mater Interfaces. 2019 May 8;11(18):16674-16682. doi: 10.1021/acsami.8b22414. Epub 2019 Apr 26.
Here we present a robust molecular precursor-based approach to synthesize high-quality thin films of silver bismuth sulfide (AgBiS). Pure-phase cubic AgBiS thin films are prepared, which are smooth and dense down to thicknesses less than 40 nm. Comprehensive structural and morphological analysis of the as-prepared films as a function of processing temperature and composition is presented, including X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The optical properties of the films and their electronic band structure are also presented. The as-prepared films show impressive light absorption properties with absorption coefficients reaching 10 cm for energies above ca. 950 nm. Finally, their photoactivity is demonstrated through photoconductivity measurements on lateral electrodes. The methods outlined herein enable the fabrication of AgBiS semiconductor thin films at low processing temperatures (150 °C) with a dense morphology and tunable Ag/Bi composition. Such films provide an excellent platform for the fabrication of AgBiS-based optoelectronic devices, specifically solar cells.
在此，我们展示了一种基于稳健分子前驱体的方法来合成高质量的硫化银铋（AgBiS）薄膜。制备出了纯相立方晶系的AgBiS薄膜，这些薄膜在厚度小于40nm时仍光滑致密。给出了所制备薄膜随加工温度和成分变化的综合结构和形态分析，包括X射线衍射、X射线光电子能谱和扫描电子显微镜。还给出了薄膜的光学性质及其电子能带结构。所制备的薄膜显示出令人印象深刻的光吸收特性，对于能量高于约950nm的光，吸收系数达到10⁵cm⁻¹。最后，通过对横向电极的光电导率测量证明了它们的光活性。本文概述的方法能够在低加工温度（150°C）下制备出具有致密形态且Ag/Bi组成可调的AgBiS半导体薄膜。这类薄膜为制造基于AgBiS的光电器件，特别是太阳能电池，提供了一个优异的平台。
