Efficient self-photo-degradation of cationic textile dyes involved triethylamine and degradation pathway

Cationic textile dyes such as astrazon brilliant red (ABR), are frequently used in the textile industry and contaminait the water ecology. Photodegradation of such dyes in wastewater is considered as a promising method, while the existing approaches are usually involved complicated and costly materials as photocatalysts. Facial, effective and low-cost approaches for their decontamination are needed. What's more, the detailed decomposition path of ABR is not revealed. The present study shows that ABR could suffer effective self-photo-degradation under triethylamine treatment without a photocatalyst. Almost 100% of the dye degraded within 1 h under visible light irradiation. UV-vis, FTIR and UPLC-MS analysis conformed the degradation of ABR. Factors involved in the degradation system were investigated clearly. What's more, the accurate and detailed analysis of UV-vis, FTIR and UPLC-MS data combined with computational analysis revealed the decomposition process of ABR. Reactive oxygen species (ROS) was investigated from ROS trapping experiments and EPR measurements, which revealed that O₂^- was the critical ROS in the degradation process, while ¹O₂ and OH had slightly influence on the degradation progression.