Abstract
The binary chalcogenide material antimony sulfide (Sb_2S_3) has attracted significant attention as a potential absorber material for photovoltaics (PVs) owing to its suitable bandgap of -1.7 eV and other unique properties. However, only a few substrate-configured Sb_2S_3 thin-film solar cells (TFSCs) have been reported, and they demonstrated an extremely low power conversion efficiency (PCE, η < 2.5%) owing to the unfavorable (hk0) orientation of Sb_2S_3. In most studies, Sb_2S_3 absorber layers were grown through physical vapor deposition or high-vacuum methods. By contrast, we used a facile hydrothermal approach to deposit Sb_2S_3 thin films on molybdenum and investigated the effect of post-deposition annealing on the structure, orientation, and morphology of Sb_2S_3 thin films. Annealing at temperatures ranging from 0° to 350°C transformed the Sb_2S_3 thin films from nearly amorphous to polycrystalline with large, horizontally aligned plate-like grains. All the annealed Sb_2S_3 thin films were confirmed to have a preferred orientation along the (hkO) crystal direction. The fabricated substrate-configured TFSCs with SLG/Mo/Sb_2S_3/CdS/i-ZnO/Al-doped ZnO/Al configuration exhibited the highest PCE of -1.0%. Further, over 95% of this initial efficiency was maintained after 90 days. We also addressed the underlying reasons for the low efficiency of Sb_2S_3 TFSCs to provide a pathway for improving the device performance in the future.
NSTL
Elsevier