Flower-like Ag/Ag2O/Bi12O17Cl2 heterojunction for photocatalytic removal of antibiotics: Synergetic effect of plasmonic effect and p–n heterojunction

The advancement of photocatalysis techniques for wastewater purification relies on the exploration of outstanding photocatalysts. Herein, a novel flower-like plasmonic p–n heterojunction of Ag/Ag₂O/Bi₁₂O₁₇Cl₂ was successfully constructed for efficient purification of antibiotic wastewater under visible light. The synergetic effect of plasmonic effect and p–n heterojunction facilitates the separation and utilization of photo-induced carriers for creation of ample reactive species, thus boosting the catalytic tetracycline hydrochloride (TC) decomposition reactions. The TC removal rate of the optimized Ag/Ag₂O/Bi₁₂O₁₇Cl₂ heterojunction is 12.6, 3.2, and 2.3 times that of single Ag₂O, Bi₁₂O₁₇Cl₂, and Ag₂O/Bi₁₂O₁₇Cl₂ respectively. The photo-induced h⁺, ·O₂⁻ and ·OH are confirmed to be the major contributors in the photocatalytic reactions. Also, the possible degradation pathways of TC are proposed, and the toxicity of the intermediates are estimated. This work offers insights into the design of plasmonic p–n photocatalysts for environmental purifications.