Afterglow-catalysis and molecular imprinting: A promising union for elevating selectivity in degradation of antibiotics

We propose a novel design for smart-catalyst to selective degrade antibiotics and self-report degradation process by combining molecular-imprinting (MI) and afterglow-catalysis. Tetracycline (TC) is used as imprinted template, and ZnGa 2 O 4 doped with Cr 3+ (ZGO) is for catalytic degradation even in-the-dark. TC-involved direct hydrothermal-growth of ZGO at 60/80 °C gives MI-ZGO, followed by 750 °C-calcination, and then ethylenediaminetetraacetic-acid (EDTA) etching to get MI-ZGO-750-EDTA. The imprinting mechanism and effect of temperature of MI-ZGO growth on degradation are investigated. The imprinting factor (IF), adsorption/degradation ratio between MI-ZGO-750-EDTA and non-imprinted NI-ZGO-750-EDTA, is used to evaluate the selectivity of three degradation modes (day-and-night, afterglow-catalysis and photo-catalysis). The highest selectivity of 60-MI-ZGO-750-EDTA is gained in afterglow-catalytic degradation, wherein IF of TC is 3 times of oxytetracycline (OTC) and 3.5 times of malachite green (MG) in pure-solutions, while in mixed-solutions, IF of TC is 3.5 times of OTC and 5.2 times of MG. Besides, photoluminescence of MI-ZGO-750-EDTA can self-report degrading process. • Selective day-night degrading tetracycline is achieved by molecularly imprinted ZGO. • Molecular imprinting & afterglow catalysis are key to improve degrading selectivity. • Molecularly imprinted ZGO can self-report the real-time degrading process.