UC San Diego

As an innovative optoelectronic material, quasi-two-dimensional (quasi-2D) perovskite has attracted huge interests due to its high stability, easily tunable bandgap and high radiative recombination efficiency, making it a perfect candidate of solar cells, LEDs and other photovoltaic devices. Although basic information exists, this material lacks a systematic and comprehensive study. Current knowledge appears fragmented, making it essential to combine insights from various sources to develop a more thorough understanding of the subject. To gain deep understanding and precise control on the crystallization of quasi-2D perovskite, we successfully engineered quasi-2D perovskite thin films on glass substrate, employing two distinct methodologies: the Direct Dissolving Method (DDM) and Redissolving Method (RM). Moreover, some of the sophisticated treatments were exerted on each method to enhance and optimize the film quality. We found that RM could possess a remarkable capability to synthesize thin films exhibiting reduced defects and superior phase purity with much lower crystallization rate when no extra treatments were applied. Concurrently, these advanced treatments were found to significantly enhance the film quality in various aspects, including surface microstructure, phase distribution, and optoelectronic properties, thereby contributing to an overall improvement of the films’ quality and efficacy.