Síntese e caracterização de nanocristais de perovskita de CsPbI 3 dopados com cobalto

Abstract

Perovskites can be formed by different combinations of chemical elements, resulting in a wide variety of structures. This structural diversity allows the production of compounds with distinct physical properties, such as ferroelectricity and pyroelectricity. Thus, the present work aims to synthesize and characterize cobalt-doped CsPbI₃ nanocrystals using the melt method. Doping with divalent metal ions has been considered an effective approach to improve external quantum efficiency due to its effect on reducing non-radiative recombination, lowering charge injection barriers, and enhancing charge carrier transport properties. Moreover, the microstructure and optical properties of the perovskite nanocrystals were characterized by Transmission Electron Microscopy, X-ray Diffraction, UV–Vis–NIR Optical Absorption Spectroscopy, and Photoluminescence. Currently, the literature reports studies on perovskites aimed at optical and electronic applications, with the vast majority focused on ABX₃ perovskites, where X generally belongs to the halogen group or corresponds to the O anion (oxygen), forming ABO₃ compounds. Therefore, in this work, a dopant strategy was developed to elucidate the internal mechanism of Co²⁺ doping, to determine its impact on the structure and properties of CsPbI₃ perovskite quantum dots, and to analyze their performance for optoelectronic applications. Finally, the authors acknowledge the Coordination for the Improvement of Higher Education Personnel (CAPES) for the financial support provided for this research, which was essential for the development of the experimental activities and for obtaining the results presented.