Yang Peipei, Zhang Hongsen, Liu Qi, Liu Jingyuan, Chen Rongrong, Yu Jing, Hou Jindi, Bai Xuefeng, Wang Jun
Key Laboratory of Superlight Material and Surface Technology, Ministry of Education, Harbin Engineering University, 150001, PR China; College of Material Science and Chemical Engineering, Harbin Engineering University, 150001, PR China.
College of Science, Harbin Engineering University, 150001, PR China.
J Hazard Mater. 2019 Aug 5;375:320-329. doi: 10.1016/j.jhazmat.2019.05.005. Epub 2019 May 3.
The introduction of organic groups onto graphene oxide (GO) platelets can supply additional active sites for adsorption of uranium(VI) (U(VI)) to improve the adsorption capacity. However, as a result of the existence of stabilizing π-conjugation system, a facile and effective modification method remains a challenge. Therefore, a novel strategy is exploited by nano-sized architectural design of multi-activity GO through post-decoration with amidoxime functionalized diaminomaleonitrile (DM-AO). The post-modification of DM-AO successfully activated the inert sites in GO platelets. Meanwhile, the amidoxime group in DM-AO can improve the adsorption selectivity. Adsorption amount of U(VI) on the as prepared GO-DM-AO reached at 935 mg g, which is increased by 209% increment compared with that of pristine GO at the same concentration. The adsorption efficiency of GO-DM-AO is greatly improved, and the time to reach the adsorption equilibrium is half of that of GO. Excitingly, the excellent removal efficiency could still maintained even after 5 cycles of adsorption-desorption. The outstanding adsorption amount, short adsorption equilibrium time, and excellent removal efficiency can provide a theoretical guidance for further immobilization of U(VI) from seawater.
在氧化石墨烯（GO）片层上引入有机基团可为吸附铀（VI）（U(VI)）提供额外的活性位点，从而提高吸附容量。然而，由于稳定的π共轭体系的存在，一种简便有效的改性方法仍然是一个挑战。因此，通过用偕胺肟功能化的二氨基马来腈（DM-AO）进行后修饰，对具有多活性的GO进行纳米结构设计，开发了一种新策略。DM-AO的后修饰成功激活了GO片层中的惰性位点。同时，DM-AO中的偕胺肟基团可以提高吸附选择性。制备的GO-DM-AO对U(VI)的吸附量达到935 mg g，在相同浓度下，与原始GO相比增加了209%。GO-DM-AO的吸附效率大大提高，达到吸附平衡的时间是GO的一半。令人兴奋的是，即使经过5次吸附-解吸循环，仍能保持优异的去除效率。出色的吸附量、较短的吸附平衡时间和优异的去除效率可为进一步从海水中固定U(VI)提供理论指导。
