Sulfur-doped carbon nitride with carbon vacancies: Enhanced photocatalytic activity for degradation of tetracycline hydrochloride

This study presents a novel approach for the synthesis of sulfur-doped g-C3N4 with carbon vacancies using thioacetamide (TAA) as the sulfur source, combined with melamine under a self-generated ammonia environment in a closed crucible. The morphological properties of the modified catalyst were characterized, revealing that carbon vacancies and sulfur-doped decreased the catalyst's forbidden bandwidth, increased surface area, enhanced absorption of visible light, and improved the separation efficiency of photogenerated carriers. The modified carbon nitride demonstrates a remarkable degradation efficiency for tetracycline hydrochloride, achieving approximately 90 % degradation after 60 min of reaction time under a 5 W LED lamp, which is 3.4 times higher than that of pure carbon nitride. Furthermore, the toxicity analysis of the solution after photocatalyst degradation was evaluated with active E. coli, and no significant effect was observed. Overall, this study provides a novel approach for the structural modification of g-C3N4, resulting in enhanced photocatalytic activity.