In this study, oxygen vacancies enriched cobalt aluminum hydroxide@hydroxysulfide (CoAl-LDH@CoS_x) hollow flowers was synthesized by in-situ etching of CoAl-LDH using sodium sulfide solution. The analysis of SEM, EDS, XRD, and XPS were used to characterize the samples. The as-synthesized 0.2CoAl-LDH@CoS_x displayed higher catalysis performance of sulfamethoxazole (SMX) degradation via the activation of PMS than the pristine CoAl-LDH. 98.5 % of SMX (40 μM) was eliminated with 0.1 g/L 0.2CoAl-LDH@CoS_x and 0.3 mM PMS at pH 6.0 in 4 min. The degradation fitted with the pseudo-first-order reaction kinetics well with rate constant of 0.89 min⁻¹ for 0.2CoAl-LDH@CoS_x/PMS system and 0.55 min⁻¹ for CoAl-LDH/PMS system. Singlet oxygen (¹O₂) was verified as dominant reactive oxygen species responsible for SMX degradation via quenching tests. Mechanism investigation suggested that the oxygen vacancies, redox cycles of Co(II)/Co(III) and S₂²⁻/(S²⁻ and sulfate species) on the surface of 0.2CoAl-LDH@CoS_x were crucial for PMS activation. In addition, the plausible degradation pathways of SMX were proposed by analysis of the SMX degradation intermediates. This study not only reveals that 0.2CoAl-LDH@CoS_x is an efficient catalyst to activate PMS for SMX degradation, but also shed a novel insight into development of heterogeneous catalysts with oxygen vacancies.

在这项研究中，通过硫化钠溶液原位蚀刻CoAl-LDH合成了富氧空位的氢氧化铝氢氧化铝（CoAl-LDH @ CoS _x）。SEM，EDS，XRD和XPS的分析用于表征样品。合成后的0.2CoAl-LDH@CoS _x与原始CoAl-LDH相比，通过PMS活化显示出更高的磺胺甲恶唑（SMX）降解催化性能。在4分钟内用0.1 g / L 0.2CoAl-LDH@CoS _x和0.3 mM PMS去除了98.5％的SMX（40μM）。对于0.2CoAl-LDH@CoS _x / PMS系统，降解与拟一级反应动力学拟合得很好，速率常数为0.89 min ^-1和0.55 min ^-1用于CoAl-LDH / PMS系统。通过猝灭测试，单重态氧（¹ O ₂）被证实是造成SMX降解的主要活性氧。机理研究表明，0.2CoAl-LDH @ CoS _x表面上的氧空位，Co（II）/ Co（III）和S ₂ ^2- /（S ^2-和硫酸盐物种）的氧化还原循环对于PMS活化至关重要。此外，通过对SMX降解中间体的分析，提出了SMX可能的降解途径。这项研究不仅揭示了0.2CoAl-LDH@CoS _x是激活PMS降解SMX的有效催化剂，而且为开发具有氧空位的多相催化剂提供了新的见识。