title: Efficient removal of heavy metal ions from aqueous systems with the assembly of anisotropic layered double hydroxide nanocrystals@carbon nanosphere.
abstract: We report on the efficient removal of heavy metal ions from simulated wastewater with a nanostructured assembly. The nanoassembly was obtained via direct assembling the performed anisotropic layered double hydroxide nanocrystals (LDH-NCs) onto the surface of carbon nanospheres (labeled as LDH-NCs@CNs). It was found that the maximum adsorption capacity of the nanoassembly toward Cu(2+) was ∼ 19.93 mg g(-1) when the initial Cu(2+) concentration was 10.0 mg L(-1), displaying a high efficiency for the removal of heavy metal ions. The Freundlich adsorption isotherm was applicable to describe the removal processes. Kinetics of the Cu(2+) removal was found to follow pseudo-second-order rate equation. Furthermore, the as-prepared building unit of the assembly, including LDH-NCs, CNs, and the assembly, as well as Cu(2+)-adsorbed assembly, were carefully examined by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), nitrogen sorption measurements, and X-ray photoelectron spectroscopy (XPS). Based on the characterization results, a possible mechanism of Cu(2+) removal with the assembly of LDH-NCs@CNs was proposed. Comparison experiments show that the adsorption capacity of the resulting LDH-NCs@CNs assembly was much higher than its any building unit alone (CNs or LDH-NCs), exhibiting the deliberation of the assembly on water decontamination. This work provides a very efficient, fast and convenient approach for exploring promising nanoassembly materials for water treatment.
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China. jmgong@mail.ccnu.edu.cn
authors.forename: Jingming
authors.initials: J
authors.lastname: Gong
authors.forename: Ting
authors.initials: T
authors.lastname: Liu
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Wang
authors.forename: Xianluo
authors.initials: X
authors.lastname: Hu
authors.forename: Lizhi
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000327:Adsorption; D016880:Anisotropy; D006878:Hydroxides / Q000737:chemistry*; D007700:Kinetics; D019216:Metals, Heavy / Q000032:analysis / Q000302:isolation & purification*; D046529:Microscopy, Electron, Transmission; D008956:Models, Chemical; D053758:Nanoparticles / Q000737:chemistry*; D054118:Nanospheres / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D017550:Spectroscopy, Fourier Transform Infrared; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D006878:Hydroxides; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical