CaMoO₄ modified nanorods-branched Ag₂MoO₄ a nano-diatomic heterojunction as efficient visible-light-driven photocatalysts for water remediation processes and antimicrobial applications

Pharmaceutically active components are one of the highly impactful environmental pollutants with toxic manifestations. The current study presents CaMoO₄-Ag₂MoO₄ nanohybrid for the photocatalytic removal of carvedilol, metronidazole, and ciprofloxacin. The formation of CaMoO₄-Ag₂MoO₄ nanohybrid was confirmed by various techniques such as HR-TEM, XPS, FT-IR, PL, XRD, BET, UV–vis DRS and EDAX. The heterojunction formed between CaMoO₄ and Ag₂MoO₄ showed effective charge separation for enhanced photodegradation of various pharmaceuticals (PhACs). The nanohybrid possessed large surface area (16 m²/g) compared with pristine CaMoO₄ and Ag₂MoO₄. CaMoO₄-Ag₂MoO₄ nanohybrid showed excellent photocatalytic degradation on various PhACs such as carvedilol, metronidazole and ciprofloxacin with photodegradation efficiency of 99.9 %, 98.5 % and 99 % respectively. Hydroxyl and superoxide radical plays a predominant role of in photodegradation of PhACs. Further, a plausible degradation pathway was determined by GC-MS analysis and the toxicity of the intermediates was evaluated by ECOSAR program. Further, the genotoxicity of the nanohybrid and toxicity of the mineralized products was studied. The stability and reusability of the nanomaterial for the photodegradation application was confirmed by six consecutive photodegradation experiments. Hence, we feel that the proposed technology can be implemented for real-time application to remove toxic pollutants.