Graphitic carbon nitride (g-C₃N₄) based photocatalysts have recently gained much attention for environmental remediation. However, the correlation between constituent counterparts in g-C₃N₄ based nanocomposites as well as mechanistic understanding related to the reactive oxygen species (ROS) have not been discussed much. Herein, ascribing to the significant thermodynamic potential of surface charge transfer between their conduction bands, we present spinel cobalt ferrite (CoFe₂O₄) decorated g-C₃N₄ nanosheets for photocatalytic mineralization of methylene blue (MB). The ROS are investigated using electron spin resonance (ESR) spectroscopy and the results confirm the formation of superoxide anion radical ($O_2^{-}$) as primary oxidant. Furthermore, UV–vis-NIR diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectroscopy (XPS) analysis are utilized to plot alignment of energy levels against standard hydrogen electrode (SHE). The band diagram does not only support the $O_2^{-}$ formation but also provides interesting insights to explain the degradation dynamics based on the respective band positions in the nanocomposite.

石墨碳氮化物（g- C ₃ N ₄）基光催化剂最近在环境修复方面引起了广泛关注。但是，基于g- C ₃ N ₄的纳米复合材料中构成对应物之间的相关性以及与活性氧（ROS）相关的机理的理解尚未得到太多讨论。在此，归因于它们的导带之间表面电荷转移的巨大热力学势，我们提出了尖晶石钴铁氧体（CoFe ₂ O ₄）装饰的g- C ₃ N ₄纳米片用于亚甲基蓝（MB）的光催化矿化。使用电子自旋共振（ESR）光谱研究了ROS，结果证实了超氧阴离子自由基（${Ø}_2^{--}$）作为主要氧化剂。此外，利用紫外可见近红外漫反射光谱（DRS）和X射线光电子能谱（XPS）分析来绘制能级与标准氢电极（SHE）的对准关系。能带图不仅支持${Ø}_2^{--}$ 的形成，但也提供了有趣的见解来解释基于纳米复合物中各个能带位置的降解动力学。