State Key Laboratory of Hydraulics and Mountain River Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, P.R. China.
Sino-German Centre for Water and Health Research, Sichuan University, Chengdu 610065, P.R. China.
Environ Sci Technol. 2023 Sep 19;57(37):14071-14081. doi: 10.1021/acs.est.3c04712. Epub 2023 Sep 8.
Currently, the lack of model catalysts limits the understanding of the catalytic essence. Herein, we report the functional group modification of model single atom catalysts (SACs) with an accurately regulated electronic structure for accelerating the sluggish kinetics of the Fenton-like reaction. The amino-modified cobalt phthalocyanine anchored on graphene (CoPc/G-NH) shows superior catalytic performance in the peroxymonosulfate (PMS) based Fenton-like reaction with Co mass-normalized pseudo-first-order reaction rate constants (, 0.2935 min), which is increased by 4 and 163 times compared to those of CoPc/G (0.0737 min) and CoO/G (0.0018 min). Density functional theory (DFT) calculations demonstrate that the modification of the -NH group narrows the gap between the d-band center and the Fermi level of a single Co atom, which strengthens the charge transfer rate at the reaction interface and reduces the free energy barrier for the activation of PMS. Moreover, the scale-up experiment realizes 100% phenol removal at 7200-bed volumes during 240 h continuous operation without obvious decline in catalytic performance. This work provides in-depth insight into the catalytic mechanism of Fenton-like reactions and demonstrates the electronic engineering of SACs as an effective strategy for improving the Fenton-like activity to achieve the goal of practical application.
目前,缺乏模型催化剂限制了对催化本质的理解。在此,我们报道了具有精确调控电子结构的模型单原子催化剂(SACs)的功能基团修饰,以加速类芬顿反应的缓慢动力学。氨基修饰的酞菁钴锚定在石墨烯上(CoPc/G-NH)在过一硫酸盐(PMS)基类芬顿反应中表现出优异的催化性能,Co 质量归一化的拟一级反应速率常数(,0.2935 min),比 CoPc/G(0.0737 min)和 CoO/G(0.0018 min)分别提高了 4 倍和 163 倍。密度泛函理论(DFT)计算表明,-NH 基团的修饰缩小了单个 Co 原子的 d 带中心和费米能级之间的差距,这加强了反应界面的电荷转移速率,并降低了 PMS 激活的自由能垒。此外,扩大规模实验在 240 h 的连续运行中实现了 100%的苯酚去除,达到 7200 床体积,而催化性能没有明显下降。这项工作深入了解了类芬顿反应的催化机制,并展示了 SACs 的电子工程作为提高类芬顿活性以实现实际应用目标的有效策略。