The graphitic carbon nitride (g-C₃N₄) with nanosheets structure or carbon vacancies is considered as the promising photocatalysts duo to their fascinating properties. Herein the carbon vacancy modified g-C₃N₄ nanosheet (TCN-600) was synthesized via one-step thermal polymerization of thiosemicarbazide precursor without auxiliary agent and extra gas protection. The higher calcination temperature and self-generating gas atmosphere (N₂H₄, CS₂ and H₂S) during the precursor polymerization impel introduction of carbon vacancies and simultaneous formation of nanosheet structures. The as-prepared TCN-600 exhibits excellent photocatalytic activity for tetracycline (TC) degradation and hydrogen production. TCN-600 shows average hydrogen production rate of 1.86 mmol g⁻¹ h⁻¹, which is 11.6 times higher than that of bulk g-C₃N₄. Meanwhile, TCN-600 displays high TC degradation efficiency of 83.3% within 90 min. The photodegradation rate of tetracycline by TCN-600 is 5.6 times higher than that by bulk g-C₃N₄. The significant improvement in photocatalytic activity is mainly attributed to its huge specific surface areas (144.5 m²/g), extended visible-light absorption, negatively shifted conduction band position, longer charge carries lifetime and faster migration of the photo-induced electron-holes. This study provides a new strategy to synthesize g-C₃N₄ with carbon vacancies and simultaneous nanosheet structure.

具有纳米片结构或碳空位的石墨氮化碳（gC ₃ N ₄）因其迷人的特性而被认为是有前途的光催化剂。在此，碳空位修饰的gC ₃ N ₄纳米片（TCN-600）是通过氨基硫脲前驱体一步热聚合合成的，无需助剂和额外的气体保护。较高的煅烧温度和自生气体气氛（N ₂ H ₄、CS ₂和 H ₂S) 在前体聚合过程中促使引入碳空位并同时形成纳米片结构。所制备的 TCN-600 对四环素 (TC) 降解和制氢表现出优异的光催化活性。TCN-600 的平均产氢率为 1.86 mmol g ^-1  h ^-1，比散装 gC ₃ N ₄高 11.6 倍。同时，TCN-600 在 90 分钟内显示出 83.3% 的高 TC 降解效率。TCN-600对四环素的光降解率是散装gC ₃ N _{4 的}5.6倍。光催化活性的显着提高主要归功于其巨大的比表面积（144.5 m² /g)，扩展的可见光吸收，负移的导带位置，更长的电荷携带寿命和光致电子空穴的更快迁移。该研究为合成具有碳空位和同时纳米片结构的gC ₃ N ₄提供了一种新策略。