Preparation of chalcogenide perovskite SrHfS3 and luminescent SrHfS3:Eu2+ thin films

As an emerging family of perovskites with S or Se anions, chalcogenide perovskites possess excellent optoelectronic properties that are comparable with halide perovskites, e.g., efficient carrier transport abilities and defect tolerance. Moreover, they are thermodynamically stable and constituted by eco-friendly elements. Among them, chalcogenide perovskite SrHfS3 is found to be a promising light emitting material and is experimentally demonstrated to be a suitable host for the luminescent lanthanide ions like Eu2+. In order to be applied in practical light emitting devices, preparation of the thin film is a critical step. Unfortunately, there are few reports on the growth of SrHfS3 thin films, hindering the knowledge of their thin film properties and applications. In this work, SrHfS3 thin films are prepared by magnetron sputtering from a commercial SrHfO3 target and subsequent sulfurization. Then, Eu2+ doping in SrHfS3 thin films is achieved by co-sputtering from a home-made EuS target. The SrHfS3 thin films exhibit high-quality crystallinity, smooth morphology, and high p-type mobility. With efficient Eu2+ doping strategy, SrHfS3:Eu2+ thin films show intensive red light, which sets foundations for their further application in practical light emitting devices.