A CuWO4/Ti3C2 MXene heterojunction with enhanced photoelectrochemical and photocatalytic performance

Abstract

Hiring photocatalysts has become one of the common and environmentally friendly methods for utilizing sunlight to eliminate pollutants and convert energy. In order to improve the photocatalytic performance of CuWO₄, in this study, we synthesized a novel hybrid CuWO₄/Ti₃C₂ MXene heterojunction via a hydrothermal route and characterized its photocatalytic and photoelectrochemical properties. The as-prepared heterostructure exhibits a significant enhancement in photocatalytic methylene blue degradation and photoelectrochemical performance (92% and 87%, respectively), compared to pure CuWO₄. This improvement is attributed to the energy band structure of the Schottky heterojunction, proposed on the basis of Mott–Schottky (M–S) plots and electrochemical impedance spectroscopy (EIS), with the measured conduction band energy of the CuWO₄/Ti₃C₂ heterostructure (0.74 V vs. NHE, pH = 7). This tailored Schottky heterojunction leads to enhanced charge transfer efficiency of photoinduced electrons from CuWO₄ to Ti₃C₂ and reduced electron–hole recombination, resulting in improved photocatalytic performance. Based on the obtained results, the CuWO₄/Ti₃C₂ heterojunction can be considered as a promising candidate for photocatalytic water treatment and energy conversion applications.