Abstract

The need for materials which aid in the production of clean energy has risen dramatically in recent years due to the looming threat of anthropogenic climate change. Perovskites have had a long history as a known material dating back to the 19th century and have seen an explosion of interest in the last 13 years as a material with great potential to oppose this threat when employed in devices for solar energy conversion. From the first perovskite-based photovoltaic to applications in photocatalysis, light emitting diodes, lasing, scintillation, and more, perovskite research moves on at a break-neck pace. Lead halide perovskites serve as the focus of much of this research as they possess unique optoelectronic properties which make them a prime candidate for application in solar energy conversion.
Though much work has been done to develop direct synthetic methods for producing lead halide perovskites, these methods offer little morphological variety, and it is well established that their optoelectronic properties are tied to their structure and morphology. As such, the present work aims to develop a synthetic procedure whereby CaCO3 microstructures are electrochemically deposited on a transparent conducting oxide glass substrate and subsequently converted to PbCO3 and then CsPbBr3, resulting in stratified microstructures with a surface layer of CsPbBr3 nanocrystals.
Lead halide perovskites also exhibit poor stability in the presence of moisture, which results in their degradation to PbX2 salts which pose a risk to the environment. Metal halide double
iv
perovskites of chemical formula A2BB'X6 have emerged as a lead-free alternative to lead halide perovskites, possessing a similar structure and comparable electronic properties. This thesis details the synthesis of Cs2NaYbCl6 as nanocrystals in order to merge the favorable optoelectronic properties of double perovskites with those associated with nanomaterials.