A novel oxygen vacancies enriched CoNi LDO catalyst activated peroxymonosulfate for the efficient degradation of tetracycline

Flower-like Co Ni layered double oxide (LDO) was successfully synthesized and applied to activate peroxymonosulfate (PMS) to degrade tetracycline (TC). Co Ni LDO was rich in oxygen vacancies (O V ) and had a high specific surface area. 30 mg/L TC was 100 % degraded in 60 min under the condition of 0.1 g/L Co Ni LDO, 1.6 mM PMS, and unadjusted pH (5.45). A reaction mechanism dominated by O V was proposed in the TC removal system. Superoxide radical and singlet oxygen played major role in the reaction system, while sulfate radical and hydroxyl radical played minor role. The anti-interference ability of the Co Ni LDO/PMS system to anions was relatively strong. At the same time, Co Ni LDO showed high recovery efficiency. The degradation efficiency of TC was still higher than 92 % after five cycles. Through the detection of degradation intermediates, a possible degradation path was proposed. This study provided an efficient approach for TC degradation and provided a new clue for improving catalytic performance by introducing O V into the catalysts in PMS-based advanced oxidation processes systems.