Simultaneous degradation of SMX for efficient nitrogen fixation to ammonia and hydrogen evolution using AgVO3@rGO-Ag3PO4 (110) heterojunction

The simultaneous degradation of organic pollutants and generation of value-added compounds like ammonia and hydrogen energy has recently gained considerable attention in photocatalysis . The present study deals with successful preparation of novel AgVO 3 nanowire@rGO-tetrahedral Ag 3 PO 4 (110) (AGA) heterojunction and utilized for enhanced generation of NH 3 and H 2 from N-containing antibiotic sulfamethoxazole (SMX) under visible light. The prepared catalyst was well characterized by XRD , SEM, TEM and XPS to confirm the formation of heterojunction . The results indicated that the composite exhibited 546.0 μmol g −1 of hydrogen evolution rate, which is approximately 3.6 (153.6 μmol g −1 ) and 5.1 (108.7 μmol g −1 ) times higher than the pure AgVO 3 and Ag 3 PO 4 respectively after 6 h. Similarly, 38.3 mg L −1 g −1 of NH 3 generation was observed during 6 h of SMX degradation, which is about 1.9 and 2.8 times higher than the pure AgVO 3 (20.1 mg L −1 g −1 ) and Ag 3 PO 4 (13.7 mg L −1 g −1 ) respectively. The formation of heterojunction between AgVO 3 and Ag 3 PO 4 not only promotes the transfer of electron but also prevents the recombination which eventually enhances the catalytic conversion of N-element to NH 3 and for H 2 generation during water splitting. Furthermore, the plausible degradation pathway in SMX was proposed and the results revealed that the SMX was mineralized by the composite further converted to NH 3 and generates H 2 during the degradation process . Thus, our study provides new insights into novel photocatalytic treatment methodologies for simultaneous degradation of SMX to produce NH 3 and H 2 as value-added compounds from antibiotic wastewaters during water treatment process.