Wang Wenhao, Xu Mengying, He Chun, Joya Muhammad Babur, Hadja Kaka Abanchime Zenaba, Kollah Emmanuel Seneway, Mwansa Blessings Kapungwe, Tremblay Pier-Luc, Zhang Tian
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan, 430070, PR China; Shaoxing Institute for Advanced Research, Wuhan University of Technology, Shaoxing, 312300, PR China.
School of Chemistry, Chemical Engineering, and Life Science, Wuhan University of Technology, Wuhan, 430070, PR China; School of Architecture and Materials Engineering, Hubei University of Education, Wuhan, 430205, PR China; Shaoxing Institute for Advanced Research, Wuhan University of Technology, Shaoxing, 312300, PR China.
Chemosphere. 2025 Mar;373:144168. doi: 10.1016/j.chemosphere.2025.144168. Epub 2025 Jan 30.
Negatively charged organic pollutants in water are responsible for a large range of public health and ecological issues. Low-cost and low-toxicity graphitic carbon nitride (CN), with its abundant functional groups and surface defects, is a promising material for the removal of organic molecules by adsorption. However, basic synthesis methods for CN often result in a material with morphology and electric charge that are suboptimal for interacting with negatively charged pollutants. Here, an adsorbent was prepared by thermally oxidizing a tubular CN precursor and then coating the resulting flake-shaped material (FCNO) with the polycationic polymer polyethyleneimine (PEI). The resulting adsorbent, FCNO-PEI, removed humic acid (HA), a widespread problematic organic molecule, as well as the common toxic anionic dye Congo red (CR). FCNO-PEI was superior to other CN-based adsorbents previously reported in the literature with maximum adsorption capacities according to the Sips isotherm model for HA and CR of 437.1 mg/g and 1430.3 mg/g, respectively. In addition, FCNO-PEI could adsorb HA and CR from different types of water and was reusable. Besides electrostatic interactions and hydrogen bonds between PEI and the pollutants, HA and CR adsorption was enabled by π-π interactions with the FCNO support itself. The high efficiency of FCNO-PEI for the removal of HA and CR highlights its potential for water treatment applications.
水中带负电荷的有机污染物会引发一系列公共卫生和生态问题。低成本、低毒性的石墨相氮化碳（CN）具有丰富的官能团和表面缺陷，是一种通过吸附去除有机分子的有前景的材料。然而，CN的基本合成方法往往导致材料的形态和电荷对于与带负电荷的污染物相互作用而言并非最优。在此，通过对管状CN前驱体进行热氧化，然后用聚阳离子聚合物聚乙烯亚胺（PEI）包覆所得的片状材料（FCNO）来制备一种吸附剂。所得的吸附剂FCNO-PEI能够去除腐殖酸（HA）（一种广泛存在的有问题的有机分子）以及常见的有毒阴离子染料刚果红（CR）。根据Sips等温线模型，FCNO-PEI对HA和CR的最大吸附容量分别为437.1 mg/g和1430.3 mg/g，优于文献中先前报道的其他基于CN的吸附剂。此外，FCNO-PEI能够从不同类型的水中吸附HA和CR，并且可重复使用。除了PEI与污染物之间的静电相互作用和氢键外，HA和CR的吸附还通过与FCNO载体本身的π-π相互作用得以实现。FCNO-PEI对HA和CR的高效去除突出了其在水处理应用中的潜力。
