Computational Study of Promising Perovskite Materials for the Application in Optoelectronic Devices

Abstract

In today s age of sustainable development, the need for advanced photovoltaic and other optoelectronic newlinedevices continues to grow rapidly. In this regard, lead halide perovskites have newlineemerged as crucial materials in fields such as solar cells, LEDs, photodetectors, lasers, and newlinemore. Conversely, the challenges of lead toxicity and material instability have created an newlineurgent demand to investigate alternative perovskites for solar energy and optoelectronic applications. newlineIn this thesis, we therefore conducted an extensive computational investigation newlineto identify promising lead-free and stable perovskite materials suitable for use in photovoltaics newlineand other optoelectronic applications. Henceforth, the thesis is structured into two newlineparts. newlineThe first part of the thesis focuses on investigating the electronic, optical, excitonic, and newlinepolaronic properties of lead-free halide double perovskites, vacancy-ordered double perovskites, newlineand Ruddlesden-Popper perovskite phases, with a particular emphasis on their potential newlineapplications in optoelectronic devices. Various strategies are employed in this part, newlineincluding the transmutation of monovalent and trivalent metal cations, anionic substitutions, newlineoctahedral vacancies, and dimensionality engineering, all aimed at improving the newlineoptoelectronic performance of these materials. This part underlines the study of the electronic newlinebandgap, optical absorption, excitonic binding energy, and polaron-induced charge newlinecarrier mobility of these stable materials, highlighting their potential for a broad spectrum newlineof optoelectronic applications. The second part delves into exploring the photovoltaic properties newlineof different chalcogenide perovskites through cationic and anionic substitutions, as newlinewell as alloying approaches. In particular, we investigated optoelectronic properties, excitonic newlinedynamics, polaronic effects, and theoretical efficiency of these materials. This part newlinereveals that the studied chalcogenide perovskites have a non-toxic elemental composition, newlineare abundant on Earth, exhibit excellent