Novel durable and recyclable Cu@MoS₂/polyacrylamide/copper alginate hydrogel photo-Fenton-like catalyst with enhanced and self-regenerable adsorption and degradation of high concentration tetracycline

A durable and recyclable Cu@MoS2/polyacrylamide/copper alginate nanocomposite double network (Cu@MoS2/PAAm/CA NCDN) hydrogel photo-Fenton-like catalyst was prepared for efficient removal of high concentration tetracycline (TC) in pharmaceutical wastewater. This hydrogel catalyst exhibits a remarkable synergistic effect between adsorption and catalytic degradation of TC. Consequently, this hydrogel catalyst shows a larger TC adsorption capacity of 122.2 mg g-1 and a higher TC degradation efficiency of 90% (degradation amount = 70.2 mg g-1) at the TC concentration of 200 mg L-1, while the TC degradation efficiency by Cu@MoS2 catalyst is only 19% (degradation amount = 38.2 mg g-1). This hydrogel catalyst can effectively remove high concentration TC under both light and dark conditions. Moreover, the tensile strength of Cu@MoS2/PAAm/CA NCDN hydrogel catalyst reaches an extraordinary 1.46 MPa and maintains 0.68 MPa after 15-day immersion in water, indicating high durability. In addition, the flexible hydrogel catalyst can keep good integrity after being deformed by stretching, bending, and knotting, etc., enabling its easy recovery. This investigation provides an innovative and versatile strategy to develop high-performance hydrogel catalysts for treating antibiotics-polluted water.