Gao Hongcheng, Fang Mengchen, Zhang Zhenzhu, Han Yi, Wang Dejin, Wang Yi, Xia Hongyu, Zhu Xiaojing, Miao Shihao, Kang Xiongwu
Key Laboratory of Aqueous Environment Protection and Pollution Control of Yangtze River in Anhui of Anhui, Provincial Education Department, College of Resources and Environment, Anqing Normal University, Anqing 246011, China.
Key Laboratory of Aqueous Environment Protection and Pollution Control of Yangtze River in Anhui of Anhui, Provincial Education Department, College of Resources and Environment, Anqing Normal University, Anqing 246011, China.
J Colloid Interface Sci. 2025 Jan 15;678(Pt A):1087-1098. doi: 10.1016/j.jcis.2024.08.245. Epub 2024 Sep 2.
Prussian blue analogs (PBAs) have attracted extensive attention in the field of aqueous organic degradation due to the tremendous potential for peroxydisulfate (PDS) activation. However, the relationship between the d-band center of the catalyst and the activation behavior of PDS remained largely unexplored. Herein, a series of Fe-Co PBAs-based catalysts with different Fe/Co ratios (Fe-Co PBAs-1 = 1: 0.52; Fe-Co PBAs-2 = 1: 1.21, and Fe-Co PBAs-3 = 1: 1.48) have been prepared by a facile hydrothermal procedure and subsequent acid treatment (Fe-Co PBAs-xH). The as-prepared Fe-Co PBAs-xH exhibited superior PDS activation performance and excellent recyclability in the degradation of methylene blue (MB). Density functional theory calculations revealed that the electron-occupied state of the Fe-Co PBAs was shifted to the Fermi level, indicating a strong interaction and easier electron transfer. Moreover, the d-band center of Fe-Co PBAs was upshifted relative to that of Fe PBAs, suggesting easier adsorption of MB and PDS, which was beneficial to enhancing catalytic activation and subsequent dissociation. Radicals such as •OH, O, O, and SO were determined by the radical quenching experiment and electron paramagnetic resonance (EPR) testing in the Fe-Co PBAs-3H/PDS system, and the order of MB degradation by the free active radical is •OH > O > O > SO. The degradation pathway and potential ecotoxicity of MB and its intermediates were also studied. This work can provide new insights to construct the efficient catalysts for the activation of PDS and the degradation of organic pollutants.
普鲁士蓝类似物（PBAs）由于在过二硫酸盐（PDS）活化方面具有巨大潜力，在水相有机降解领域引起了广泛关注。然而，催化剂的d带中心与PDS活化行为之间的关系在很大程度上仍未得到探索。在此，通过简便的水热法和后续酸处理（Fe-Co PBAs-xH）制备了一系列具有不同Fe/Co比的基于Fe-Co PBAs的催化剂（Fe-Co PBAs-1 = 1: 0.52；Fe-Co PBAs-2 = 1: 1.21，以及Fe-Co PBAs-3 = 1: 1.48）。所制备的Fe-Co PBAs-xH在亚甲基蓝（MB）降解中表现出优异的PDS活化性能和出色的可回收性。密度泛函理论计算表明，Fe-Co PBAs的电子占据态向费米能级移动，表明存在强相互作用且电子转移更容易。此外，Fe-Co PBAs的d带中心相对于Fe PBAs上移，表明对MB和PDS的吸附更容易，这有利于增强催化活化及随后的解离。通过自由基猝灭实验和电子顺磁共振（EPR）测试在Fe-Co PBAs-3H/PDS体系中确定了诸如•OH、O、O和SO等自由基，并且由游离活性自由基导致的MB降解顺序为•OH > O > O > SO。还研究了MB及其中间体的降解途径和潜在生态毒性。这项工作可为构建用于活化PDS和降解有机污染物的高效催化剂提供新的见解。
