Herein, a new type of peroxymonosulfate (PMS) activator—phosphorus-doped carbon nitride (P-C₃N₄)—was prepared using a one-step thermal shrinkage method. Material characterisation confirmed the successful doping of phosphorus in graphite-phase carbon nitride (g-C₃N₄) by replacing the carbon atoms in its triazine ring structure to form PN bonds. Phosphorus doping can regulate and re-organise the surface electronic structure of g-C₃N₄ without changing its structure. Moreover, phosphorus doping promotes varying degrees of optimisation of the g-C₃N₄ pore structure and electronic transport between the g-C₃N₄ sites. Batch experiments on tetracycline (TC) degradation revealed that 0.2 P-C₃N₄ showed the best physicochemical properties, the constructed P-C₃N₄/PMS system exhibited high TC removal efficiency and P-C₃N₄ exhibited good reusability and structural stability. Quenching experiments and electron paramagnetic resonance tests revealed that singlet oxygen was the primary active species in the P-C₃N₄/PMS system. The mechanism of PMS activation using P-C₃N₄ was then proposed. The analysis of TC and its intermediate products using liquid chromatography–mass spectroscopy demonstrated that TC was primarily degraded via ring-opening, hydroxylation, deamination and dealkylation reactions. Analysis using the toxicity estimation software tool demonstrated that most intermediate products were less toxic than TC. Thus, this study provides a feasible method for removing TC from aquatic environments.

在此，采用一步热收缩法制备了一种新型过一硫酸盐（PMS）活化剂——磷掺杂氮化碳（PC ₃ N _{4 ）。}材料表征证实，通过取代三嗪环结构中的碳原子形成 P N 键，成功地将磷掺杂到石墨相氮化碳 (gC ₃ N _{4 ) 中。磷掺杂可以在不改变gC 3} N ₄结构的情况下调节和重组其表面电子结构。_{此外，磷掺杂促进了gC 3} N ₄孔结构和gC ₃之间电子传输不同程度的优化。N _{4 个}站点。批量降解四环素（TC）实验表明，0.2 PC ₃ N ₄表现出最好的理化性质，构建的PC ₃ N ₄ /PMS系统表现出较高的TC去除效率，PC ₃ N ₄表现出良好的可重复使用性和结构稳定性。_{淬火实验和电子顺磁共振测试表明单线态氧是PC 3} N ₄ /PMS体系中的主要活性物质。_{使用 PC 3} N ₄激活 PMS 的机制然后被提议。使用液相色谱-质谱法对TC及其中间产物进行分析表明，TC主要通过开环、羟基化、脱氨和脱烷基反应进行降解。使用毒性估计软件工具进行的分析表明，大多数中间产品的毒性低于原药。因此，本研究为去除水生环境中的TC提供了一种可行的方法。