New Ti/CNT/CNT-Ce-PbO anode synergy peroxymonosulfate activation for efficiently electrocatalytic degradation of p-aminobenzoic acid.

Increased levels of p-aminobenzoic acid in aquatic environments, primarily utilized as UV filter in sunscreens, poses a serious threat to human and ecosystem health, while there is a dearth of exhaustive researches pertaining to the efficient and cost-effective elimination of p-aminobenzoic acid. Herein, a Ti/SnO-Sb/CNT-α-PbO/CNT-Ce-β-PbO, referred to Ti/CNT/CNT-Ce-PbO electrode was constructed by incorporating CNTs into the middle layer of PbO electrode, and simultaneously doping CNTs and Ce in the active layer. A series of tests signify that the target electrode is successfully fabricated, which exhibits higher particle density and smaller particle size, as well as exceptional degradation performance for p-aminobenzoic acid with a degradation rate of 99.7% within 30 min coupling with peroxymonosulfate activation. The optimal degradation performance was observed at a PMS dosage of 0.07 g, NaSO concentration of 0.05 mol L, current density of 120 mA cm, and initial pH value of 6.94. Capture experiments, electron spin resonance test, liquid chromatography-mass spectrometry analysis, toxicity assessment and theoretical calculation were performed to clarify the main activate radicals, degradation pathways and intermediate toxicity. This study provides a new anode material, and conducted the first exploration of electrocatalysis integrating peroxymonosulfate activation for degradation p-aminobenzoic acid.