title: Hydrothermal synthesized magnetically separable mesostructured H2Ti3O7/γ-Fe2O3nanocomposite for organic dye removal via adsorption and its regeneration/reuse through synergistic non-radiation driven H2O2activation.
abstract: Hydrogen titanate (H2Ti3O7) nanotubes/nanosheets (HTN) are emerging class of adsorbent material which possess unique property of activating hydrogen peroxide (H2O2) to generate the reactive oxygen species (ROS), such as superoxide radical ions (O2.-) and hydroxyl radicals (·OH), effective in the decomposition of surface-adsorbed dye. However, HTN are non-magnetic which create hurdle in their effective separation from the treated aqueous solution. To overcome this issue, magnetic nanocomposites (HTNF) composed of HTN and maghemite (γ-Fe2O3) nanoparticles have been processed by subjecting the core-shell magnetic photocatalyst consisting of γ-Fe2O3/silica (SiO2)/titania (TiO2), having varying amounts of TiO2in the shell to the hydrothermal conditions. HTNF-5 magnetic nanocomposite consisting of 31 wt% H2Ti3O7, typically having nanotube morphology with the highest specific surface area (133 m2g-1) and pore-volume (0.22 cm3g-1), exhibits the highest capacity (74 mg g-1) for the adsorption of cationic methylene blue (MB) dye from an aqueous solution involving the electrostatic attraction mechanism and pseudo-second-order kinetics. Very fast magnetic separation followed by regeneration of HTNF-5 magnetic nanocomposite has been demonstrated via non-radiation driven H2O2activation. It has been ascertained for the first time that the underlying mechanism of dye decomposition involves the synergy effect between the constituents of HTNF magnetic nanocomposite.
authors.affiliation: Functional Materials Section (FMS), Materials Science and Technology Division (MSTD), Council of Scientific and Industrial Research (CSIR), CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India.|Academy of Scientific and Innovative Research (AcSIR), CSIR-NIIST Campus, Thiruvananthapuram, Kerala, 695019, India.
authors.forename: Harsha
authors.initials: H
authors.lastname: Narayani
authors.affiliation: Functional Materials Section (FMS), Materials Science and Technology Division (MSTD), Council of Scientific and Industrial Research (CSIR), CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India.|Academy of Scientific and Innovative Research (AcSIR), CSIR-NIIST Campus, Thiruvananthapuram, Kerala, 695019, India.
authors.forename: Manu
authors.initials: M
authors.lastname: Jose
authors.affiliation: Functional Materials Section (FMS), Materials Science and Technology Division (MSTD), Council of Scientific and Industrial Research (CSIR), CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India.
authors.forename: K
authors.initials: K
authors.lastname: Sriram
authors.affiliation: Functional Materials Section (FMS), Materials Science and Technology Division (MSTD), Council of Scientific and Industrial Research (CSIR), CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India. satyajit_shukla@niist.res.in.|Academy of Scientific and Innovative Research (AcSIR), CSIR-NIIST Campus, Thiruvananthapuram, Kerala, 695019, India. satyajit_shukla@niist.res.in.
authors.forename: Satyajit
authors.identifier: http://orcid.org/0000-0002-7947-8095
authors.initials: S
authors.lastname: Shukla
mesh_terms: D000327:Adsorption; D004396:Coloring Agents; D005290:Ferric Compounds; D006861:Hydrogen Peroxide; D007501:Iron; D007700:Kinetics; D008280:Magnetics; D008751:Methylene Blue; D053761:Nanocomposites; D043942:Nanotubes; D017382:Reactive Oxygen Species; D012822:Silicon Dioxide; D014025:Titanium; D014874:Water Pollutants, Chemical; D018508:Water Purification / Q000379:methods*
chemical_list: D004396:Coloring Agents; D005290:Ferric Compounds; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; C000499:ferric oxide; D012822:Silicon Dioxide; D006861:Hydrogen Peroxide; D014025:Titanium; D007501:Iron; D008751:Methylene Blue
keywords: Adsorption; Dye; Isotherm; Kinetics; Magnetic separation; Reactive oxygen species; Recycling