Speaker
Description
Over the last few decades, perovskite-type compounds (ABX₃) have attracted considerable scientific interest owing to their remarkable structural versatility and wide range of functional properties. Despite the apparent simplicity of the ideal perovskite crystal structure, this class of materials exhibits enormous compositional and structural flexibility, giving rise to a variety of intriguing physical and chemical properties. Consequently, they find applications in many fields, including catalysis, electrocatalysis, electronics, energy conversion and storage, sensing, and information technologies. Depending on their composition and structure, they may exhibit ferroelectricity, piezoelectricity, high-temperature superconductivity, colossal magnetoresistance, and many other technologically relevant properties. More recently, hybrid organic–inorganic perovskites have emerged as a new generation of semiconducting materials with outstanding performance in photovoltaic and optoelectronic applications.
The first part of this lecture will provide a general overview of the perovskite structure, major classes of perovskite materials, commonly used synthesis methods, and selected functional properties. The second part will focus on our research on complex inorganic perovskites synthesized by the solution combustion method using different fuels. Their crystal structures were refined by the Rietveld method using powder X-ray diffraction (PXRD) data, while various crystallographic parameters related to structural stability and distortion were calculated and analyzed. Structural, compositional, morphological, electrical, and electrocatalytic properties were systematically investigated using complementary characterization techniques. Particular attention was devoted to understanding how structural and microstructural factors influence the electrical conductivity and electrocatalytic performance of the synthesized materials, especially in reactions relevant to sustainable energy technologies, such as the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).
The final part of the lecture will present selected results from our studies on bulk materials and thin films of hybrid organic–inorganic lead halide perovskites containing different organic cations. Their composition, crystal structure, morphology, optical properties, and electrochemical stability were investigated. Optical band-gap energies were determined from UV–Vis absorption spectra of the thin films using Tauc analysis, and the potential of these materials for photovoltaic applications was evaluated.
Keywords: perovskites, solution combustion synthesis, crystal structure, electrocatalysis, hybrid organic–inorganic perovskites, photovoltaic applications