Synergistic activation of peroxymonosulfate for tetracycline hydrochloride degradation with SrTiO3/Ti3C2Tx photocatalyst

Abstract

Peroxymonosulfate (PMS) is a promising technology for increasing the oxidation capacity and promoting the production of active species in the photocatalytic system. SrTiO3, a material with a perovskite crystal structure in a cubic form, can activate PMS on its surface and generate non-radical 1O2. Herein, SrTiO3/Ti3C2Tx (ST) composites were successfully synthesized using a hydrothermal method based on SrTiO3 materials. The photocatalytic activation of PMS resulted in the degradation of tetracycline hydrochloride (TC-HCl), with the ST-10 (10 wt% SrTiO3/Ti3C2Tx) composite showing the highest efficiency in TC removal and rapid degradation kinetics, achieving complete TC removal within 10 min. The synergistic interaction between the two components in ST-10 significantly enhanced the activation of peroxymonosulfate (PMS), leading to an increased production of free radicals. The larger specific surface area and presence of –OH groups in the composite material facilitated the adsorption and chemical bonding of PMS molecules, thereby improving their overall performance. Quench experiments and electron paramagnetic resonance analysis identified •SO4−, •OH, •O2– and 1O2 as the primary active species responsible for the degradation of TC. Additionally, the degradation pathway of TC was elucidated through mass spectrometry analysis. This study provides valuable insights for the development of effective photocatalysts as promising PMS catalysts in environmental applications.