title: Unique lead adsorption behavior of activated hydroxyl group in two-dimensional titanium carbide.
abstract: 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.
authors.affiliation: 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.
authors.forename: Qiuming
authors.initials: Q
authors.lastname: Peng
authors.forename: Jianxin
authors.initials: J
authors.lastname: Guo
authors.forename: Qingrui
authors.initials: Q
authors.lastname: Zhang
authors.forename: Jianyong
authors.initials: J
authors.lastname: Xiang
authors.forename: Baozhong
authors.initials: B
authors.lastname: Liu
authors.forename: Aiguo
authors.initials: A
authors.lastname: Zhou
authors.forename: Riping
authors.initials: R
authors.lastname: Liu
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Tian
mesh_terms: D000327:Adsorption; D006878:Hydroxides / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D006878:Hydroxides; C096521:titanium carbide; C031356:hydroxide ion; D014025:Titanium