SOLUTION PROCESSED SNO₂–TIO₂ HETEROJUNCTION NANOCOMPOSITES FOR ENHANCED PHOTOCATALYTIC DEGRADATION AND ELECTROCHEMICAL ENERGY STORAGE APPLICATIONS

Abstract

The unique properties of heterojunction nanocomposites, including enhanced charge separation, superior photocatalytic activity, and improved electrochemical performance, have attracted significant attention for environmental remediation and energy storage applications. In this study, a SnO₂-doped TiO₂ nanocomposite was successfully synthesized via a simple solution-based method. The structural and phase characteristics of the synthesized nanocomposite were investigated using X-ray diffraction (XRD) and Raman spectroscopy, while the morphology and microstructure were examined by transmission electron microscopy (TEM). The photocatalytic activity was evaluated using methylene blue (MB) as a model organic dye under UV irradiation. In addition, the electrochemical performance of the nanocomposite was systematically investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) to assess its charge storage capability and charge-transfer characteristics. The SnO₂-doped TiO₂ nanocomposite exhibited excellent photocatalytic efficiency, achieving 94% degradation of MB within 120 min. The enhanced photocatalytic and electrochemical performances are attributed to the formation of an effective SnO₂/TiO₂ heterojunction, which promotes efficient separation and transport of photogenerated electron–hole pairs, reduces charge recombination, and lowers the interfacial charge-transfer resistance, as confirmed by the EIS analysis. These findings demonstrate that the SnO₂-doped TiO₂ nanocomposite is a promising multifunctional material for both photocatalytic pollutant degradation and electrochemical energy storage applications.