Synthesis of nano-sized Ag3PW12O40/ZnO heterojunction as a photocatalyst for degradation of organic pollutants under simulated sunlight

Abstract

With the rapid development of the world economy, water pollution has become increasingly serious. The photocatalytic degradation of pollutants is one of the most promising environmental treatment techniques. In this study, novel Ag3PW12O40/ZnO nanoheterojunction was successfully constructed via a chemical process and was then characterized using X-ray diffraction, transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, diffuse reflectance spectroscopy, Brunauer-Emmett-Teller analysis, and photoluminescence measurements. The synthesized nanoheterojunction exhibited good crystallinity and dispersity. The particle diameter of the composite was approximately 800 nm, the bandgap was 2.92 eV, and the specific surface area was approximately 10.5 m2.g−1. Under optimum conditions, the photocatalyst degraded 82.1% RhB in 60 min. Moreover, the novel Ag3PW12O40/ZnO heterojunction also exhibited an excellent recycling stability. Hydroxyl radicals, superoxide radicals, and holes played important roles in the photocatalytic degradation process. A possible mechanism for the enhanced photocatalytic performance of the nanoheterojunction was proposed. This work provides a strong foundation for the application of Ag3PW12O40/ZnO nanoheterojunction for treating environmental organic pollutants.

Keywords

• Ag3PW12O40/ZnO
• Nanoheterojunction
• Photocatalyst
• Organic pollutant