Hydrothermal Synthesis of the CuWO4/ZnO Composites with Enhanced Photocatalytic Performance

Photocatalytic technology aiming to eliminate organic pollutants in water has been rapidly developed. In this work, we successfully synthesized CuWO4/ZnO photocatalysts with different weight ratios of CuWO4 through facile hydrothermal treatment. Crystal structures, forms, and optical properties of these as-prepared materials were investigated and analyzed. 3% CuWO4/ZnO showed the optimum photodegradation efficiency toward methylene blue under the irradiation of simulated sunlight for 120 min, the degradation rate of which was 98.9%. The pseudo-first-order rate constant of 3% CuWO4/ZnO was similar to 11.3 and similar to 3.5 times bigger than that of pristine CuWO4 and ZnO, respectively. Furthermore, the material exhibited high stability and reusability after five consecutive photocatalytic tests. In addition, free radical capture experiments were conducted and the possible mechanism proposed explained that the synergistic effect between CuWO4 and ZnO accelerates the photodegradation reaction. This work provides a feasible technical background for the efficient and sustainable utilization of photocatalysts in wastewater control.