Min Chen1 Yuanyuan Zhou1 Minggang Ju2 Xiao Cheng Zeng2 Nitin Padture1

1, Brown University, Providence, Rhode Island, United States
2, University of Nebraska, Lincoln, Lincoln, Nebraska, United States

Perovskite solar cells (PSCs) based on lead-containing hybrid organic-inorganic halide perovskites have demonstrated great promise as a new photovoltaic technology for the clean-energy future. However, the toxicity and the phase stability of these perovskites are of significant concern. In this context, we have theoretically predicted and experimentally validated a new group of all-inorganic halide perovskites based on the environmentally-friendly and earth-abundant element, titanium (Ti(IV)), which possess ideal optical bandgaps for solar cells. Further, we have developed low-temperature facile methods for fabricating high-quality Ti-based halide perovskite thin films. The physical properties of the as-prepared Ti-based halide perovskite thin films are measured, suggesting their superior potential in PSC applications. The formation mechanisms of these Ti-based halide perovskites and device physics of Ti-based PSCs are also studied extensively, the understanding from which provides guidance for further boosting the performance of Ti-halide-based PSCs.