DFT исследование гибридной структуры BaTiO3/g-C3N4

Abstract

Annotation. In recent decades, carbon graphite nitride (g-C₃N₄), a bimetallic polymer organic semiconductor with tri-s-triazine units, has been a promising research topic due to its optimal photocatalytic properties and unique characteristics such as a suitable band structure, visible light absorption activity, and high chemical and thermal stability. However, the photocatalytic efficiency of pure g-C₃N₄ limits its use in photocatalytic systems due to the high recombination rate of photogenerated charges, insufficient light absorption, and small specific surface area. The combination of graphite carbon nitride with perovskites provides a good opportunity to correct these deficiencies.  In this study, the theoretical modeling of the g-C₃N₄/BaTiO₃ hybrid structure was considered. A (100) surface was created from the cubic phase of barium titanate. For (100) BaTiO₃ surfaces, it was found that a TiO₂-terminated surface is more thermodynamically favorable. The relaxation process of the hybrid structure was investigated. The developed interface is thermodynamically stable, which provides prerequisites for its further application for photogeneration of energy in various processes based on redox reactions. Тhermodynamic stability of the BaTiO₃/g-C₃N₄ nanocomposite can be explained by the interaction of BaTiO₃ nanoparticles with g-C₃N₄ through the Ti-N bond, a decrease in the band gap due to the introduction of hybridized states leading to increased absorption in the visible range, and a large surface area that provides more active sites for effective light absorption.