Abstract: The use of solar photocatalytic degradation of pollutants is one of the most promising technologies to solve water
pollution problems and achieve solar energy conversion. By changing the amount of g⁃C₃N₄ added, g⁃C₃N₄4/Co3O4 catalysts with
different g⁃C₃N₄ mass fractions are prepared based on the calcination method with cobalt nitrate hexahydrate (Co（NO₃)₂•6H₂O) and
urea (NH₄CNO) as raw materials. The samples are analyzed and characterized using X⁃ray diffraction（XRD）, X⁃ray photoelectron
spectroscopy（XPS）and ultraviolet visible absorption spectroscopy（UV vis DRS）. To speculate on the active species of the
catalyst, capture agent experiments are conducted on it. The results indicate that the synergistic effect between g⁃C₃N₄ and Co₃O₄
can improve the transfer and separation efficiency of charge carriers at the interface between the two phases. Under visible light,
the degradation effect of 10% g⁃C₃N₄/Co₃O₄ is the best, with a degradation rate of 66.5%, which is higher than the degradation
effect of single Co₃O₄（degradation rate of 35.9%）. The active species of the catalyst are mainly superoxide radicals（•O₂^—）and
holes（h+）. After compounding with g⁃C₃N₄, the drawbacks of Co3O4 electron hole pair, such as too fast recombination and a
deficient energy level structure, are improved, providing ideas for the degradation of organic pollutants in the future.

Key words: Photocatalysis, Cobalt tetroxide, Tetracycline, Heterojunction, Graphite nitride carbon

摘要： 利用太阳能光催化降解污染物，是解决水污染问题并实现太阳能转化最有前途的技术之一。应用
煅烧法，以六水合硝酸钴（Co（NO₃）₂·6H₂O）、尿素（NH₄CNO）为原料，通过改变 g⁃C₃N₄的加入量，制备了 g⁃C₃N₄质
量分数不同的 g⁃C₃N₄/Co₃O₄催化剂；利用 X 射线衍射（XRD）、X 射线光电子能谱（XPS）、紫外⁃可见吸收光谱（UV⁃vis
DRS）测试，对催化剂进行了分析和表征；为推测催化剂的活性物种，对其进行了捕获剂实验。结果表明，g⁃C₃N₄与
Co₃O₄的协同作用可提高两相界面间载流子的转移和分离效率；在可见光下，g⁃C₃N₄质量分数为 10% 的 g⁃C₃N₄/
Co₃O₄对四环素的降解效果最佳，降解率为 66.5%，高于纯 Co₃O₄对四环素的降解率（35.9%）；催化剂的活性物种主要
为超氧自由基（·O₂^-）和空穴（h+）；Co₃O₄与 g⁃C₃N₄的复合，改善了 Co₃O₄电子⁃空穴对复合过快、带隙小和光吸收能力弱
等不足，为今后有机污染物的降解提供了思路。

关键词: 光催化, 　四氧化三钴, 　四环素, 　异质结, 　石墨氮化碳