Study on the photo-assisted activation of PMS by CuMo1−xWxO4 for degradation of tetracycline†

Abstract

In this study, a series of CuMo_1−xW_xO₄ solid solutions (CMWO) were prepared by adjusting the ratio of Mo to W. The morphology, phase, specific surface area, and valence state of the catalysts were characterized using SEM, TEM, XRD, BET, and XPS analysis. The photoelectric characteristics of the CuMo_1−xW_xO₄ solid solution materials were analyzed in detail using Mott–Schottky, EIS, PL, and UV-vis DRS analysis. The experimental results show that the energy band structure of the CMWO solid solutions can be tuned to inhibit the carrier recombination under light excitation, thereby facilitating effective electron–hole pair separation. This significantly enhances the performance of photo-assisted PMS activation for tetracycline (TC) degradation. The solid solution material CMWO-3, with a Mo/W ratio of 7 : 3, achieved a TC degradation rate of 88% at pH 5. After five cycles, the TC degradation rate remained at 86%. Throughout the reaction process, photocatalysis and PMS activation exhibited a synergistic effect, generating reactive species such as SO₄˙⁻, ˙OH, ¹O₂, and ˙O₂⁻.