title: General facile approach to transition-metal oxides with highly uniform mesoporosity and their application as adsorbents for heavy-metal-ion sequestration.
abstract: Mesoporous powders of transition-metal oxides, TiO2, ZrO2, HfO2, Nb2O5, and Ta2O5, pure from organic impurities were produced by a rapid single-step thermohydrolytic approach. The obtained materials display an impressively large active surface area and sharp pore-size distribution, being composed of partially coalesced uniform nanoparticles with crystalline cores and amorphous shells. They reveal extremely high adsorption capacity in removal of Cr(VI) anions from solutions (25.8 for TiO2, 73.0 for ZrO2, and 74.7 mg g(-1) for Nb2O5 in relation to the Cr2O7(2-) anion), making them very attractive as adsorbents in water remediation applications. The difference in adsorption capacities for the studied oxides may be explained by variation in surface hydration and surface-charge distribution.
authors.affiliation: Department of Chemistry and Biotechnology, BioCenter, Swedish University of Agricultural Sciences, Box 7015, 75007 Uppsala (Sweden). Gulaim.Seisenbaeva@slu.se.
authors.forename: Gulaim A
authors.initials: GA
authors.lastname: Seisenbaeva
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Daniel
authors.forename: Vadim G
authors.initials: VG
authors.lastname: Kessler
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Nedelec
mesh_terms: D000327:Adsorption; D002857:Chromium / Q000737:chemistry / Q000302:isolation & purification; D049329:Nanostructures / Q000737:chemistry*; D009556:Niobium / Q000737:chemistry; D010087:Oxides / Q000737:chemistry; D016062:Porosity; D014025:Titanium / Q000737:chemistry; D028561:Transition Elements / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry
chemical_list: D010087:Oxides; D028561:Transition Elements; D014874:Water Pollutants, Chemical; D009556:Niobium; D002857:Chromium; C009495:titanium dioxide; C074702:chromium hexavalent ion; D015040:Zirconium; D014025:Titanium; C073337:niobium pentoxide; C028541:zirconium oxide
keywords: mesoporous oxides; nanostructures; sorption mechanism; thermohydrolysis; transition metals