Fabrication of CuMn2O4/Co3O4 nanocomposite heterojunctions for efficacious visible light-induced degradation of antibiotics

The synthesis and design of heterojunction nanocomposites with remarkable photocatalytic performance remains a challenge. In this work, the fabrication of CuMn2O4/Co3O4 nanocomposite heterojunctions has been addressed for efficacious visible-light-induced degradation of tetracycline (TC). A facile sol-gel strategy with soft template assistance was utilized to synthesize mesoporous Co3O4 frameworks and then CuMn2O4 NPs were impregnated to obtain mesoporous CuMn2O4/Co3O4 nanocomposites. TEM images of CuMn2O4/Co3O4 nanocomposite revealed a homogeneous shape with a particle size of 10 nm. The degradation efficiency of CuMn2O4/Co3O4 nanocomposites exhibited significant enhancement and achieved 100% within 75 min. The 9%CuMn2O4/Co3O4 photocatalyst exhibited the highest TC degradation ability, which was enhanced 1.6 times that of pure Co3O4 NPs, and its rate constant was up to 2.35-times compared with the pure Co3O4 NPs. The photocatalytic ability of CuMn2O4/Co3O4 nanocomposites was significantly promoted due to their construction of heterojunction, the synergistic effect between CuMn2O4 and Co3O4, the enlarged surface area, strengthened effective charge mobility and narrowed bandgap energy. The CuMn2O4/Co3O4 nanocomposite was reusable and quite stable during the TC photodegradation process, even after five times repeatedly. This work shows research ideas and technical approaches for the photodegradation of antibiotics during the construction of heterojunction nanocomposites.