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Heterostructure composite catalysts have shown great potential in activating peroxymonosulfate (PMS) to effectively remediate organic contaminants. However, the construction of high-performance composites with a heterostructure interface using simple and rapid strategies remains a challenge. This study introduces a straightforward and environmental-friendly approach to prepare NiCo/CoNiO2heterojunction integrated carbon nanotubes (NiCo/CoNiO2@CNTs) through a solid-phase microwave carbon bath process, where CNTs serve as a substrate and microwave adsorption material. The NiCo/CoNiO2@CNTs/PMS system demonstrates exceptional performance, achieving a removal rate of 95.9 % within 30 min in degrading tetracycline (TC) with PMS activation. Synergistic effects between the CoNi alloy and CoNiO2promote the Co3+/Co2+and Ni3+/Ni2+redox cycles, boosting the catalyst’s activity and reusability. Moreover, the NiCo/CoNiO2@CNTs/PMS system demonstrates high resistance to various solution pH levels, inorganic anions and humic acid. The catalytic oxidation of TC involves radical and non-radical pathways, with the latter dominating the degradation process. Three possible pathways generate thirteen intermediate products during TC destruction. Toxicity assessment reveals a significant reduction in the toxicity of TC-contaminated water after degradation over the system. The current study not only presents an effective strategy for fabricating heterojunction composite materials but also offers an efficient oxidation system for remediating antibiotic pollutants.

Construction of effective multi-component composite materials via architecture modulation to destruct antibiotic pollutants through activating peroxymonosulfate (PMS) remains a challenge. In this study, we report a two-step hydrothermal process to construct MoS2nanosheets integrated with transition metal sulfide (CoS2, Cu2S and MnS) nanoparticles for activating PMS towards degrading emerging tetracycline (TC) antibiotic. Among the samples, CoS2@MoS2is verified as the best PMS activator for TC destructing with a removal rate of 95.3% in 30 min. The CoS2@MoS2/PMS system also performs well under various reaction conditions. The dominant reactive oxygen species responsible for TC degradation is identified as 1O2. Furthermore, CoS2@MoS2-catalyzed PMS efficiently degrades TC into eleven intermediates via three possible pathways. The toxicity of these intermediates is evaluated, both in terms of acute/chronic toxicity and phytotoxicity. The presence of Mo4+sites on the catalyst surface facilitates the rapid transfer of electrons from MoS2to Co3+, promotes the regeneration of Co2+, and facilitates the redox cycle of Co3+/Co2+. Therefore, the synergistic effects between CoS2and MoS2are responsible for the efficient degradation of TC over the CoS2@MoS2/PMS system. This study establishes an architecture engineering strategy for preparing dual transition metal sulfides, which synergistically promote PMS activation towards the degradation of organic pollutants.