WO_3-x nanorods/rGO/AgBiS₂ Z-scheme heterojunction with comprehensive spectrum response and enhanced Fenton and photocatalytic activities

Tetracycline (TC) antibiotics and dyes are the prevalent water contaminants, and their removal from the water through photocatalysis is a plausible approach. However, most semiconductors in their pristine form need to be improved to be exploited in photocatalysis owing to poor photoresponse, intense carrier recombination, and inertness without irradiation. Herein, we demonstrate the modification of defective WO_3-x by rGO and AgBiS₂ in the form of WO_3-x/rGO/AgBiS₂ (R₂). It exploits the superior conductivity and synergism of rGO to inhibit carrier recombination; thereby, Z-scheme heterojunction with AgBiS₂ provides high redox potential. Defects in WO_3-x enable electron (e^-) storage in R₂, which decomposes H₂O₂ to generate ROS without irradiation. Owing to these essences and broad-spectrum response, it removed 93.72, 82.77, and 84.82% of TC during photo-Fenton (PFR), night-Fenton (NFR), and photocatalytic (PCR) reactions, respectively. Its removal rates reached 94.74, 81.54, and 87.50% against rhodamine B (RhB) during PFR, NFR, and PCR, respectively. It is superior to memory catalysis (MC) and conventional Fenton reactions (CFR) because it can perform without and with irradiation across a broader pH range. So, this work is conducive to designing WO_3-x-based catalysts to combat environmental and energy crises.