Photoassisted activation of persulfate by Cu2(OH)2CO3 for the degradation of tetracycline hydrochloride

Cu2(OH)2CO3 (cupric carbonate basic, CCB) is a common copper-based semiconductor compound that can absorb the visible light due to its suitable bandgap structure. Here, CCB was synthesized by a one-pot hydrothermal strategy. The catalyst exhibited excellent activation activity of persulfate (PS) supported by visible light irradiation and can degrade tetracycline hydrochloride (TCH) over a wide pH range from 3.0 to 10.0. Under the condition of 0.1 g/L catalyst and 2 mM PS, the removal rate of TCH (30 mg/L) reached 96% after 60 min of visible light irradiation. Coexisting anions (Cl- , HCO3 - , SO4 2- ) had little effect on the TCH degradation. The synergistic effects of CCB combined with PS and visible light were beneficial for the separation of photogenerated hole-electrons and the generation of more free radicals. Electron paramagnetic resonance (EPR) experiments and quenching experiments show that HO∙ and h+ are the predominant species in the catalytic reaction. Thus, this study proposes a promising approach using the CCB/PS/Vis system for wastewater remediation.