RGO-ZnTe: A Graphene Based Composite for Tetracycline Degradation and Their Synergistic Effect

For a high-performance photocatalyst, efficient exciton formation and subsequent dissociation, effective interfacial charge separation, and transportation to the photocatalytic reduction active sites are highly desired. Here, the visible-light-responsive reduced graphene oxide-zinc telluride (RGO-ZnTe) photocatalyst was synthesized by a single-pot one-step solvothermal process. Analysis of chemical compositions and structural and morphological characterization of the as-synthesized RGO-ZnTe samples were carried out intensively by TGA, XRD, XPS, TEM, and SEM study. Efficient transport of photoinduced electrons from ZnTe to RGO through their interface is confirmed by photoluminescence (PL) study. It is observed that the RGO mats are well-decorated with ZnTe nanoparticles, where RGO acts as a solid support as well as a nucleation center of the ZnTe nanocrystal. The RGO-ZnTe composite exhibited higher (6 times compared to RGO and 2.6 times compared to ZnTe) photocatalytic efficiency toward the visible-light-driven photodegradation of tetracycline (TC) antibiotics. Efficient catalytic performance is ascribed to better interaction and synergy among RGO and ZnTe. In the RGO-ZnTe composite the 2D wrinkled surface of RGO has a vital role in receiving the enhanced performance of ZnTe nanoparticle by minimizing the recombination probabilities of the photoinduced electron–hole. The responsible reactive species for photocatalytic TC degradation are also investigated comprehensively, which confirms that both holes and oxygen radicals have a dominating role toward the degradation of TC.