Bandgap Tuning in BaZrS<sub>3</sub> Perovskite Thin Films
Shyam Sharma, Zachary D. Ward, Kevin Bhimani, Kang Li, Aniruddha S. Lakhnot, Rishabh Jain, Su‐Fei Shi, Humberto Terrones, Nikhil Koratkar
Abstract
Chalcogenide perovskites (such as BaZrS3) are gaining increasing attention for solar cells due to their lead-free nature and superior environmental stability. However, a major limitation of BaZrS3 is that its bandgap (∼1.75 eV) is significantly larger than the ideal bandgap (∼1.34 eV) required to achieve the maximum theoretical efficiency for a single-junction photovoltaic cell. In this study, we demonstrate the reduction in bandgap from 1.75 to 1.4 eV through in situ alloying of titanium (Ti) during chemical vapor deposition growth, forming BaZr1–xTixS3 thin films. Theoretical study showed good agreement with experimental observations, demonstrating feasibility of bandgap tuning of BaZrS3 films.