Graphitic Carbon Nitride/V₃O₇ Nanocomposites with Antibacterial Property via Photocatalytic and Nanozyme Activities

The increasing prevalence of bacterial issues and the misuse of antibiotics have emerged as significant contemporary problems that demand attention. Hence, there is an urgent need for the development of antibiotic-free, efficient, and environmental antibacterial technologies as well as the establishment of an advanced platform for antibiotic detection and analysis. In this study, graphitic carbon nitride/V 3 O 7 nanocomposites (VCNs) with a unique heterojunction structure were synthesized by the chemical precipitation method. VCN not only exhibits remarkably high peroxidase (POD)-like activity but also possesses a favorable band structure. This endows VCN with a broader visible light absorption range and enables effective suppression of the recombination of photogenerated electron–hole pairs, thereby significantly enhancing its photocatalytic activity. With the synergistic effect of photocatalysis and nanozyme catalysis, the “white” plus “black” antibacterial effect of “1 + 1 > 2” has been successfully realized. Therefore, VCN exhibits highly efficient, environmental, and broad-spectrum antibacterial activity (>99.9%). In addition, based on the unique nature of VCN oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB), a colorimetric sensing array was successfully constructed that can extract multichannel information from a single reaction element. The feasibility of this array has been demonstrated in the analysis and detection of tetracycline antibiotics (TCs) within complex environments. This not only provides unique insights into the development of nanomaterials with photocatalytic and nanozyme activities but also offers innovative and sustainable solutions for antibacterial activity and effective monitoring of TCs.