College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, P. R. China.
Materials Research Institute, School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK.
Chemistry. 2019 Dec 18;25(71):16340-16349. doi: 10.1002/chem.201903875. Epub 2019 Nov 21.
Nanomaterials play a significant role in adsorption treatment of dye wastewater, but irreversible aggregation of nanoparticles poses a significant problem. In this work, nanomesoporous zinc-doped silicate (NMSZ) was prepared by an in situ method. To prevent agglomeration, NMSZ was covalently bonded to graphene oxide (GO) sheets to form a nano-silica/zinc/graphene oxide composite (GO-NMSZ), aimed at removal of cationic dye methylene blue (MB). For comparison, undoped mesoporous silica (MS) was also synthesized and modified to obtain a silica/graphene oxide composite (GO-MS). The materials were characterized by powder XRD, SEM, FTIR spectroscopy, TEM, nitrogen sorption, and X-ray photoelectron spectroscopy (XPS). Preservation of the oxygen-containing groups of GO in the composites led to higher adsorption capacities. The best GO-NMSZ composite exhibited an enhanced adsorption capacity of 100.4 mg g for MB compared to those of undoped GO-MS (80.1 mg g ) and nongrafted NMSZ (55.7 mg g ). The nonselective character of GO-NMSZ is demonstrated by effective adsorption of anionic dye Congo red (127.4 mg g ) and neutral dye isatin (289.0 mg g ). The adsorption kinetics, adsorption isotherms, and a thermodynamic study suggested that MB adsorption occurs by chemisorption and is endothermic in nature.
纳米材料在染料废水吸附处理中起着重要作用，但纳米粒子的不可逆聚集是一个重大问题。本工作采用原位法制备纳米介孔锌硅酸盐（NMSZ）。为防止团聚，将 NMSZ 共价键合到氧化石墨烯（GO）片上，形成纳米二氧化硅/锌/氧化石墨烯复合材料（GO-NMSZ），旨在去除阳离子染料亚甲基蓝（MB）。为了进行比较，还合成并修饰了未掺杂的介孔二氧化硅（MS）以获得二氧化硅/氧化石墨烯复合材料（GO-MS）。通过粉末 XRD、SEM、FTIR 光谱、TEM、氮气吸附和 X 射线光电子能谱（XPS）对材料进行了表征。复合材料中保留了 GO 的含氧基团，从而提高了吸附容量。最佳 GO-NMSZ 复合材料对 MB 的吸附容量为 100.4 mg g，而未掺杂的 GO-MS（80.1 mg g）和未接枝的 NMSZ（55.7 mg g）的吸附容量更高。GO-NMSZ 的非选择性特征通过对阴离子染料刚果红（127.4 mg g）和中性染料靛红（289.0 mg g）的有效吸附得到证明。吸附动力学、吸附等温线和热力学研究表明，MB 的吸附是通过化学吸附发生的，本质上是吸热的。
Zotero 插件