Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100086, China.
Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100086, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
J Hazard Mater. 2021 Jan 5;401:123261. doi: 10.1016/j.jhazmat.2020.123261. Epub 2020 Jun 22.
Iron-nickel bimetallic organic frameworks (FeNi-BDC, HBDC: terephthalic acid) were developed as bifunctional materials for adsorption and photo-Fenton degradation of organic dyes with different charge properties. Significantly enhanced adsorption capacity of FeNi-BDC towards methylene blue (MB) and methyl orange (MO) was achieved, 5.3 and 2.6 times higher than that of pristine Fe-BDC, which was attributed to enlarged specific surface area and pore volume and the decreased surface charges induced by Ni doping. The adsorption kinetics demonstrated that chemisorption was dominant and intra-particle diffusion was the rate-controlling step. Two-stage degradation including slow induction stage and rapid oxidation stage fitted with pseudo-zero-order kinetics well. The increased rate constants (2.472 vs. 1.188 min for MB; 0.616 vs. 0.421 min for MO) in the induction stage as well as the superior removal capability by asynchronism relative to synchronism jointly corroborating the improved adsorption performance was favor for subsequent degradation. Notably, this heterogeneous system not only exhibited obvious advantages like wider pH working range (3-9), better stability and reusability of catalysts, but also achieved the dual objectives of in-situ decontamination and adsorbent regeneration. The coupling of adsorption and degradation along with synergism between photocatalysis and Fenton-like process are responsible for the reinforced removal of organic contaminants.
铁-镍双金属有机骨架（FeNi-BDC，HBDC：对苯二甲酸）被开发为具有不同荷电性的有机染料吸附和光芬顿降解的双功能材料。FeNi-BDC 对亚甲基蓝（MB）和甲基橙（MO）的吸附容量显著提高，分别是原始 Fe-BDC 的 5.3 倍和 2.6 倍，这归因于比表面积和孔体积的增大以及 Ni 掺杂引起的表面电荷降低。吸附动力学表明，化学吸附占主导地位，内扩散是速率控制步骤。两段式降解包括缓慢诱导阶段和快速氧化阶段，与准零级动力学拟合良好。在诱导阶段，速率常数增加（MB 的 2.472 对 1.188 min；MO 的 0.616 对 0.421 min），异步相对于同步的去除能力更强，这共同证明了改进的吸附性能有利于随后的降解。值得注意的是，这种非均相体系不仅具有更宽的 pH 工作范围（3-9）、催化剂更好的稳定性和可重复使用性等明显优势，而且还实现了原位净化和吸附剂再生的双重目标。吸附和降解的结合以及光催化和类芬顿过程之间的协同作用是增强去除有机污染物的原因。
