Preparation of MnO2/BiVO4 composite photocatalyst materials applied in landscape-water purification design of elderly community

Abstract

Antibiotic contaminants such as tetracycline hydrochloride (TC) in landscape water of elderly communities threaten health. Antibiotics degradation in water purification leads to better environment. TC degradation by heterojunction nanocomposite for activating peroxymonosulfate (PMS) is significant. Here, MnO₂/BiVO₄ nanocomposite catalysts were prepared by sonication and heat treatment. MnO₂ particles with 6–8 nm of size were uniformly distributed on BiVO₄ to favor rapid recombination of electron/hole pairs to improve the efficiency of PMS activation. Photocatalytic system with MnO₂/BiVO₄ nanocomposite catalyst achieved efficient TC degradation. Optimal TC degradation conditions were [catalyst] = 0.2 g, [PMS] = 0.15 g and pH = 7. Electron paramagnetic resonance (EPR) and scavenger studies verified the occurrence of ·OH, SO₄^·−, ¹O₂, h⁺, ·O₂⁻ and e⁻ species and positive contribution of MnO₂/BiVO₄ nanocomposite to PMS activation. MnO₂/BiVO₄ nanocomposite exhibits good reusability in catalytic reactions. This work provides suitable photocatalytic materials for TC treatment in senior community landscape water.