Oxygen vacancies mediated electrons transfer for the degradation of organic pollutants in UV/layered double oxides/thiourea dioxide

Due to the increasing deterioration of the aqueous environment caused by various organic dyes, the development of highly efficient novel photocatalysts has become urgent. This study designed a novel UV/layered double oxides (LDO)/thiourea dioxide (TD) system based on UV-assisted advanced reduction processes to achieve efficient and cost-effective degradation of methyl orange (MO). The experimental results exhibited that 99.7% of 50 mg/L MO was completely degraded in UV/LDO/TD within 20 min at 25 °C and pH 10. During the decomposition of TD, highly reductive e aq − , SO 2 2− and H· were generated, and in the presence of dissolved oxygen simultaneously produced oxidizing species such as O 2 ·− , OH·, and 1 O 2 . Oxygen vacancies of LDO not only activated TD but also acted as an electron shuttle to transfer electrons from TD to MO. Non-radical degradation pathways, including 1 O 2 and electron transfer process, dominated the degradation of MO. The degradation efficiency of MO remained at 93.2% after 5 cycles, demonstrating the excellent reusability of LDO in the UV/LDO/TD system. This study provided new insights into LDO-activated TD under UV irradiation for environmental remediation. It highlighted the commercial potential of the UV/LDO/TD system for sustainable, scalable removal of organic dyes from industrial wastewater.