Sustainable photodegradation of tetracycline by surface-functionalized carbon nitride: Mechanism insight and toxicity assessment

Abstract

Here, we report the facile preparation of amino- and vacancies-abundant carbon nitride photocatalyst using acetone as a low-boiling-point solvent and describe its successful performance of environmental purification. As a demonstration of the notion, tetracycline (TC) antibiotic as an emerging aqueous contaminant has been used as a model substrate for assessing the photoactivity of the modified carbon nitride and clarifying its intrinsic mechanism. 96 % of TC can be photocatalytically removed within 30 min, accompanied by a discernible mitigation in ecotoxicological impact. Reactive species, including •OH, •O2-, and photogenerated holes, are considered the critical oxidants. Meanwhile, the possible intermediates and transformation pathways of TC degradation were investigated utilizing the LC-MS technique, the Fukui function, and the T.E.S.T. software. The comprehensive approach furnishes valuable insights for assessing the evolutionary dynamics of tetracycline in an advanced oxidation process (AOP). This study offers a sustainable, cost-effective, and eco-friendly approach to preparing carbon nitride material, which is believed to open an avenue for the facile design of heterogeneous environmental photocatalysts and to provide insights into the various environmental applications.