Ag-doped TiO2 immobilized cellulose-derived carbon beads: One-Pot preparation, photocatalytic degradation performance and mechanism of ceftriaxone sodium

Photocatalytic degradation is a promising method to solve the problem of ceftriaxone sodium wastewater. In this paper, Ag/TiO2@C composite materials with different Ag molar contents, where cellulose-derived carbon beads used as the carrier, were successfully prepared by the One-Pot method. In Ag/TiO2@C composite photocatalyst, Ag nanoparticles were deposited on TiO2 particles to form a metal-semiconductor structure, where charge carriers were effectively separated under the Surface Plasmon Resonance effect of Ag nanoparticles, thereby extending the lifetime of charge carriers. Ag/TiO2@C has been found of higher photocatalytic degradation performance compared to pure TiO2 and pure carbon beads. Among all, Ag (0.5%)/TiO2@C has the best catalytic performance. According to the Langmuir-Hinshelwood model, the photodegradation rate followed first-order kinetics, with the highest apparent rate of 0.0091 min−1. According to the results of mass spectrometry, ceftriaxone sodium was degraded into small molecules and eventually degraded into CO2, H2O, and we proposed possible pathways and photocatalytic mechanism accordingly.