In this work, electron-withdrawing groups functionalized few layer graphitic carbon nitride (FCN-12) nanosheet was prepared and utilized for photocatalytic activation of peroxymonosulfate (PMS). Experimental characterization and density functional theory (DFT) calculation reveals that the electronic structure of FCN-12 is efficiently adjusted by forming an upward band bending, as the functionalized carbonyl (C=O) and carboxyl (-COOH) groups can withdraw the electron from the C-N=C skeleton. With the addition of PMS, FCN-12 displays superb photocatalytic activity for chlortetracycline hydrochloride (CTC) degradation, where 83.4% CTC can be degraded within 120 min under visible light irradiation, much higher than that of bulk g-C₃N₄ (34.3%). Besides, even under the different pH condition and co-existed anions environment, FCN-12/PMS/vis system still exhibits favorable applicability. The boosted catalytic performance is resulted from the collective effect of the few-layer feature and the energy band bending, which leads to the effective migration of photogenerated electron from FCN-12 to PMS via C=O and -COOH groups. This work not only provides an exhaustive insight into the role of energy band bending in electron-withdrawing group functionalized g-C₃N₄, but also paves the avenue for the development of metal-free photocatalyst-mediated environmental remediation based on PMS activation.

在这项工作中，吸电子基团功能化的几层石墨氮化碳（FCN-12）纳米片制备并用于过氧单硫酸盐（PMS）的光催化活化。实验表征和密度泛函理论（DFT）的计算表明，FCN-12的电子结构可通过形成向上的能带弯曲而得到有效调节，因为官能化的羰基（C = O）和羧基（-COOH）可将电子从CN = C骨架。通过添加PMS，FCN-12对盐酸金霉素（CTC）的降解显示出了极好的光催化活性，其中在可见光照射下，在120分钟内可降解83.4％的CTC，远高于块状gC ₃ N _4。（34.3％）。另外，即使在不同的pH条件和阴离子共存的环境下，FCN-12 / PMS / vis体系仍具有良好的适用性。催化性能的提高归因于多层特征和能带弯曲的共同作用，这导致光生电子通过C = O和-COOH基团从FCN-12有效迁移到PMS。这项工作不仅为能带弯曲在吸电子基团官能化的gC ₃ N _4中的作用提供了详尽的见解，而且还为基于PMS活化的无金属光催化剂介导的环境修复的发展铺平了道路。