Synthesis of ZnO Co-doped Ph-g-C3N4for enhanced photocatalytic organic pollutants removal under visible light

The paper deals with the synthesis of a binary ZnO/Ph-g-C(3)N(4)nanocomposite, a highly efficient visible light active catalyst for the photodegradation of organic pollutants in aqueous suspension by single-step calcination and combustion process. The synthesised materials have been characterised using different techniques such as X-ray diffraction, UV-Vis, FTIR, SEM-EDX, and TEM. The UV-Vis DRS analysis indicates 20-30 nm red-shift and a decrease in bandgap from 3.1 to 2.7 eV on doping ZnO with Ph-g-C(3)N(4.)The photocatalytic activity of the prepared nanocomposites was tested by studying the degradation of two different chromophoric dyes, rhodamine B (RhB) and methyl orange (MO) and a drug derivative, Paracetamol. The composite, 0.05% ZnO/Ph-g-C(3)N(4,)displayed the best activity for the degradation of both dyes and the drug. The trapping and quenching studies indicate that both hydroxyl and superoxide radical anions are responsible for the degradation of pollutants under investigation. The higher photocatalytic activity of the prepared samples could be attributed to the generation of heterojunction between the Ph-g-C(3)N(4)and ZnO, which is the response for improved light absorption and efficient separation of the photo-excited electron and hole pair.

Automated summary

The paper presents the synthesis of a binary ZnO/Ph-g-C(3)N(4) nanocomposite and its highly efficient visible light catalytic activity for the degradation of organic pollutants in water. Characterization techniques were used to study the synthesized materials, revealing a red-shift and decrease in bandgap when ZnO was doped with Ph-g-C(3)N(4). The nanocomposite showed excellent degradation activity for two dyes and a drug, with the involvement of hydroxyl and superoxide radical anions in the degradation process. The improved photocatalytic activity was attributed to the generation of a heterojunction between Ph-g-C(3)N(4) and ZnO, leading to enhanced light absorption and efficient separation of photo-excited electron-hole pairs.