State Key Laboratory of Metastable Materials Science and Technology, ‡Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University , Qinhuangdao 066004, PR China.
J Am Chem Soc. 2014 Mar 19;136(11):4113-6. doi: 10.1021/ja500506k. Epub 2014 Mar 10.
The functional groups and site interactions on the surfaces of two-dimensional (2D) layered titanium carbide can be tailored to attain some extraordinary physical properties. Herein a 2D alk-MXene (Ti3C2(OH/ONa)(x)F(2-x)) material, prepared by chemical exfoliation followed by alkalization intercalation, exhibits preferential Pb(II) sorption behavior when competing cations (Ca(II)/Mg(II)) coexisted at high levels. Kinetic tests show that the sorption equilibrium is achieved in as short a time as 120 s. Attractively, the alk-MXene presents efficient Pb(II) uptake performance with the applied sorption capacities of 4500 kg water per alk-MXene, and the effluent Pb(II) contents are below the drinking water standard recommended by the World Health Organization (10 μg/L). Experimental and computational studies suggest that the sorption behavior is related to the hydroxyl groups in activated Ti sites, where Pb(II) ion exchange is facilitated by the formation of a hexagonal potential trap.
二维（2D）层状碳化钛表面的官能团和位相互作用可以进行剪裁，以获得一些非凡的物理性质。在此，通过化学剥离后进行碱插层制备的二维烷氧基-MXene（Ti3C2(OH/ONa)(x)F(2-x)）材料，在共存高水平竞争阳离子（Ca(II)/Mg(II)）时表现出优先的 Pb(II)吸附行为。动力学测试表明，吸附平衡在短短 120 秒内即可达到。引人注目的是，烷氧基-MXene 表现出高效的 Pb(II)摄取性能，应用吸附容量为每烷氧基-MXene 4500 公斤水，流出液中的 Pb(II)含量低于世界卫生组织（10 μg/L）推荐的饮用水标准。实验和计算研究表明，吸附行为与活化 Ti 位的羟基有关，其中 Pb(II)离子交换通过形成六边形位阱而得到促进。
