Tailored synthesis of Ag/AgBr nanostructures coupled activated carbon with intimate interface interaction for enhanced photodegradation of tetracycline

Photocatalytic mechanism of AABR-ACK 7 composite. [Display omitted] •Ordered Ag/AgBr nanostructures on activated carbon (AABR-ACK) were synthesized.•Synthesized AABR-ACK composites were optimized for the degradation of tetracycline.•RSM shows that effect of time and temperature on removal of TC were significant.•Contact between ordered AABR and ACK aid photo-prompted charge carriers separation. Tailored synthesis of Ag/AgBr nanostructures (AABR) with intimate interface interaction for enhanced photocatalytic performance is a challenge for its extensive applications. Herein, tailored Ag/AgBr nanostructures promoted with char-microwave activated carbon (ACK) was synthesized through a modified deposition-precipitation method. The influence of four reaction parameters comprising of a mass of surfactant, temperature, ACK mass and ammonium hydroxide volume for the AABR-ACK composites were optimized using response surface methodology (RSM). Their simultaneous interactions on removal efficiency of tetracycline (TC) antibiotics under visible light were investigated under visible light. The high photocatalytic degradation of TC over AABR-ACK composites was governed by ammonium hydroxide volume and temperature. The SEM, XRD, FTIR, TEM, optical and electrochemical properties of the composites from these influential parameters, evidenced the formation of tailored AABR-ACK nanostructures with intimate interface interaction. The tailored near spheres nanostructures of AABR promoted with ACK boosted the visible light absorption, intimate interface contact, which promotes photo-induced charge pairs separation for the enhanced visible-light photocatalytic activity of AABR-ACK 7 composite TC (87 %). In addition, AABR-ACK 7 composite possessed significant recycle efficiency up to four consecutive cycles. The mineralization efficiency of AABR-ACK 7 on TC achieved 78.5 % and possible degradation pathways of TC were proposed. This work offers good insight into the tailored design of visible-light responsive heterojunction photocatalysts for sustainable environmental remediation.