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At least 667 records · Page 37
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Testing the stability of magnetic iron oxides/kaolinite nanocomposite under various pH conditions

Magnetically modified clays containing iron oxides nanoparticles (Fe{sub x}O{sub y} NPs) are low-cost and environmentally harmless materials suitable for sorption of pollutants from wastewaters. Stability of this smart material was evaluated both experimentally and theoretically using molecular modelling. Original kaolinite and prepared Fe{sub x}O{sub y}/kaolinite nanocomposite were characterized using X-ray fluorescence spectroscopy, X-ray powder diffraction, infrared spectroscopy, and transmission electron microscopy, and the stability was studied using leaching tests performed according to the European technical standard EN 12457-2 in deionized water and extraction agents with varying pH (2, 4, 9, and 11). The influence of pH on amount of Fe{sub x}O{sub y} NPs released from the composite and amount of the basic elements released from the kaolinite structure was studied using inductively coupled plasma atomic emission spectroscopy. All experiments proved that the magnetic properties of the nanocomposite will not change even after leaching in extraction agents with various pH. - Graphical abstract: The stability of magnetic Fe{sub x}O{sub y}/kaolinite nanocomposite was studied using molecular modelling and leaching tests under various pH conditions. Display Omitted - Highlights: • Magnetization by Fe{sub x}O{sub y} nanoparticles did not influenced the structure of the kaolinite. • Maghemite (γ-Fe{sub 2}O{sub 3}) and mainly magnetite (Fe{sub 3}O{sub 4}) phases were detected. • Leaching test confirmed good adhesion of Fe{sub x}O{sub y} nanoparticles on kaolinite. • Molecular modelling of kaolinite/Fe{sub x}O{sub y} nanocomposite agrees well with experiments. • Nanocomposite can be considered stable in the wide range of pH.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

An investigation of the electronic, structural and magnetic properties of the ruddlesden-popper phase Sr{sub 3}RuCoO{sub 7}

The structural, magnetic and electronic properties of the Ruddlesden-Popper material Sr{sub 3}CoRuO{sub 7} have been investigated. Examination of the dc and ac magnetic susceptibility demonstrates that Sr{sub 3}CoRuO{sub 7} exhibits a spin glass transition at 40 K and a magnetic transition at 140 K. Variable-temperature neutron powder diffraction experiments showed no evidence of magnetic diffraction peaks down to 5 K. This suggests the transition at 140 K is a result of short range magnetic order or magnetic clustering of the Co/Ru spins. Sr{sub 3}CoRuO{sub 7} is semiconducting and Mott variable range hopping behaviour is observed below 240 K. - Graphical abstract: Short range antiferromagnetic order is observed below ∼ 140 K in Sr{sub 3}CoRuO{sub 7} followed by spin glass behaviour at 40 K. Display Omitted.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Diatom influence on the production characteristics of hydrate-bearing sediments: Examples from Ulleung Basin, offshore South Korea

The Ulleung Basin Gas Hydrate field expeditions in 2007 (UBGH1) and 2010 (UBGH2) sought to assess the Basin's gas hydrate resource potential. Coring operations in both expeditions recovered evidence of gas hydrate, primarily as fracture-filling (or vein type) morphologies in mainly silt-sized, fine-grained sediment, but also as pore-occupying hydrate in the coarser-grained layers of interbedded sand and fine-grained systems. A commonality across many of these occurrences is the presence of diatoms in the fine-grained sediment. Here we tested fine-grained sediment (median grain size <12.5 μm) associated with hydrate occurrences at four UBGH2 sites (UBGH2-2-2, UBGH2-3, UBGH2-6 and UBGH2-11) to investigate potential impacts of diatoms on efforts to extract methane from hydrate, or to tap hydrocarbon reservoirs beneath hydrate-bearing sediment. Two key considerations are: the extent to which diatoms control sediment mechanical properties, and the extent to which pore-water freshening, which occurs as gas hydrate breaks down during resource extraction, alters the diatom control on sediment mechanical properties. We conducted experiments to measure sediment index properties, sedimentation behavior and compressibility to address these considerations. We relied on scanning electron microscope (SEM) imagery and X-ray powder diffraction (XRD) to characterize the sediment mineralogy. Our high-level findings are that at the ~20–45% (by volume) diatom concentrations observed at these UBGH2 sites, sediment compressibility increases with diatom content, but diatoms only appear to increase porosity and permeability at the highest diatom concentration (~45%). Our measurements suggest in situ compression indices of 0.35–0.55 and permeabilities on the order of 0.01milliDarcies (1 × 10 -17 m 2 ) can be anticipated at these sites. Importantly, these properties are not expected to vary significantly upon pore water freshening that accompanies gas hydrate dissociation during production.

58 GEOSCIENCES↗
DOE OSTI2014

Properties, characterization, and decay of sticky rice–lime mortars from the Wugang Ming dynasty city wall (China)

Urgent restoration of the Wugang Ming dynasty city wall brings about the need for a study of the formulation and properties of mortars. In the present paper, mortar samples from the Wugang Ming dynasty city wall were characterized in a combination of sheet polarized light optical microscopy, scanning electron microscopy with X-ray energy dispersive spectrometer, thermogravimetric/differential scanning calorimetry, X-ray powder diffraction, Fourier transform infrared spectroscopy, and inductively coupled plasma emission spectroscopy. Results show that mortars are mainly built up from inorganic calcium carbonate based organic–inorganic hybrid material with a small amount of sticky rice, which plays a crucial role in forming dense and compact microstructure of mortars and effectively hindering penetration of water and air into mortars. Analysis of decayed products shows that the detrimental soluble salts originates from ambient environment. - Highlights: • Mortars used in the Wugang city wall are a calcium carbonate-sticky rice hybrid bonding material. • Carbonation processing is extremely slow due to dense and compact microstructure of mortars. • Decying of mortars results from the appearance of soluble salt from ambient environment.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Formation of less-known structurally complex ζ{sub b} and orthorhombic quasicrystalline approximant ε{sub n} on solidification of selected Al–Pd–Cr alloys

The evolution of phases was investigated on cooling of Al{sub 71}Pd{sub 24}Cr{sub 5}, Al{sub 73}Pd{sub 20}Cr{sub 7}, and Al{sub 73}Pd{sub 23}Cr{sub 4} alloys from 1350 °C down to ambient temperature with the rate of 10 °C·min{sup −1}. To perform the investigation, differential thermal analysis, synchrotron X-ray powder diffraction, and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy were used. In all the investigated alloys structurally complex phases ε{sub n} (ε{sub 6} + ε{sub 28}) and ζ{sub b}, as well as the δ-phase were identified. Based on the results of differential thermal analysis, sequences of phase transformations were determined. The Al{sub 71}Pd{sub 24}Cr{sub 5} alloy started to solidify at 1031.4 °C through β. Primary dendrites of ζ{sub b} were observed in Al{sub 73}Pd{sub 20}Cr{sub 7} and Al{sub 73}Pd{sub 23}Cr{sub 4} alloys. In the second step of solidification δ and/or ζ{sub b} were formed. The peritectic reaction, liquid + ζ{sub b} + δ → ε{sub n} + ζ{sub b} + δ, leading to the formation of the quasicrystalline approximant ε{sub n} (ε{sub 6} + ε{sub 28}) took place in the final step of solidification at approximately 792 °C. - Highlights: • Structurally complex ε{sub n} (ε{sub 6} + ε{sub 28}), ζ{sub b} and δ-phases were identified. • The Al{sub 71}Pd{sub 24}Cr{sub 5} alloy started to solidify at 1031.4 °C through the primary β phase. • The Al{sub 73}Pd{sub 20}Cr{sub 7} and Al{sub 73}Pd{sub 23}Cr{sub 4} alloys solidified in the same way. • The quasicrystalline approximant ε{sub n} (ε{sub 6} + ε{sub 28}) was formed at approximately 792 °C.

36 MATERIALS SCIENCE↗
DOE OSTI2018

New compositional data on ancient mortars and plasters from Pompeii (Campania – Southern Italy): Archaeometric results and considerations about their time evolution

Highlights: • Mortar samples from Pompeii, with different constructive functions, were studied. • Characterization of the materials can be used for preparing compatible mortars. • Analogies and differences were highlighted to identify the constructive phases. • Preliminary statistic models were proposed to discriminate materials and constructive phases. Twenty-six samples of mortar used for various construction applications (joint mortars, floor mortars, filling mortars and plasters) were collected from different areas of the archaeological site of Pompeii (Campania - Sothern Italy). The mortar samples belong to various historical periods covering approximately 2000 years, from the 2nd century BC to the post excavation period (18–19th century). The samples were characterized employing Optical Microscopy (OM), X-ray Powder Diffraction (XRPD), X-ray Fluorescence (XRF), Electron Probe Micro Analysis (EPMA) and Raman Spectroscopy. Moreover, image analysis was carried out using JMicroVision software in order to determine the percentages of binder, macropores and aggregate, in terms of crushed ceramic fragments (cocciopesto), rock fragments and monocrystals. The application of these techniques allowed obtaining a complete chemical and minero-petrographic characterization of the samples, which may prove useful for preparing compatible repair mortars for future restoration works. The archaeometric study provided new data on the production technology of the mortars and the analogies and differences observed among the samples, enabled us to distinguish different constructive phases, thus confirming or rebutting the archaeological hypothesis on the dating of some samples. By combining compositional variables through the discriminant analysis, it was also possible to analyse the time evolution of the materials and to construct preliminary multivariate statistical models, helpful to identify the various typologies of mortars used in the different historical periods.

36 MATERIALS SCIENCE↗
DOE OSTI2020

XRD and SEM/EDS characterization of two quaternary fuel alloys (U-2.5Mo-2.5Ti-5.0Zr and U-1.5Mo-1.5Ti-7.0Zr in wt. %) for fast reactors

The current study focuses on characterization of two potential fuel alloys for sodium-cooled fast reactors: U-2.5Mo-2.5Ti-5.0Zr (U-MT5Z) and U-1.5Mo-1.5Ti-7.0Zr (U-MT7Z) in wt. %. As-cast alloys and annealed (600°C, 500h) alloys are studied by X-ray powder diffraction (XRD) for their bulk structures, and scanning electron microscopy / energy dispersive X-Ray spectroscopy (SEM/EDS) for their microstructures and phase constituents. For as-cast alloys, the XRD results show that U-MT5Z mainly contains γ, while U-MT7Z alloy contains a. In both alloys, there are three phases indicated by EDS, a U-rich phase, secondary phase, and Zr-rich phase. Further, the elemental compositions varied in different phases and in different alloys. After annealing, both alloys exhibit the structures of α-U and U 2 Ti according to XRD. The EDS results suggest there are five phases found in both alloys.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2014

Structure-property relationships along the Fe-substituted CuInS 2 series: Tuning of thermoelectric and magnetic properties

CuIn 1-x Fe x S 2 (x = 0–0.15) was synthesized via high-temperature, solid-state synthesis. Rietveld refinements using the neutron and synchrotron powder diffraction data indicate that all Fe-substituted materials are phase pure with the exception of the CuIn 0.85 Fe 0.15 S 2 sample, which contains a minute secondary phase. These refinements also verify that iron resides on the indium site in the CuIn 1-x Fe x S 2 materials. CuIn 0.875 Fe 0.125 S 2 displayed the lowest total thermal conductivity of the series, 1.37 W m -1 K -1 at 570 K, as well as the highest thermopower, -172 μV K -1 at 560 K. The electrical conductivity increases over six times upon going from CuInS 2 to CuIn 0.875 Fe 0.125 S 2 . These improved properties result in an increase in the thermoelectric figure of merit (ZT) of CuInS 2 by over an order of magnitude for the x = 0.125 sample. Magnetic measurements reveal the x = 0–0.10 samples to be paramagnetic, while the sample in which x = 0.125 displays ferromagnetic ordering below 95 K.

Burnett, Johanna D.↗
DOE OSTI2015

Structural and magnetic properties of nickel antimony ferrospinels

Spinel-type compounds of Fe–Ni–Sb–O system were synthesized as polycrystalline powders. The crystal and magnetic properties were investigated using X-ray and neutron powder diffraction, Mössbauer and X-ray absorption spectroscopy and magnetization measurements. The samples crystallize in the cubic system, space group Fd – 3 m. The distribution of cations between octahedral and tetrahedral sites was refined from the diffraction data sets using constraints imposed by the magnetic, Mössbauer and EDS results and the ionic radii. The cation distribution and the temperature dependence of the lattice parameter (a) and the oxygen positional parameter (u) were obtained. A chemical formula close to Fe0.8Ni1.8Sb0.4O4 was determined, with Sb5+ cations occupying octahedral sites, and Fe3+ and Ni2+ occupying both tetrahedral and octahedral sites. Fe3+ mainly (85/15 ratio) occupy tetrahedral sites, and conversely Ni2+ mainly reside on octahedral ones. The magnetic unit cell is the same as the crystallographic one, having identical symmetry relations. The results indicate that the compounds have a collinear ferrimagnetic structure with antiferromagnetic coupling between the tetrahedral (A) and octahedral (B) sites. Uniquely, the temperature dependence of the net magnetization of this rare earth free ferrimagnet exhibits a compensation point.

Crystal structure↗
DOE OSTI2013

Facile synthesis of Cu/Cu{sub x}O nanoarchitectures with adjustable phase composition for effective NO{sub x} gas sensor at room temperature

Graphical abstract: The Cu/Cu{sub x}O nanoarchitectures with 30–70 nm hollow nanospheres reduced by 3 mmol NaBH{sub 4} exhibits excellent gas-sensing property to low-concentration NO{sub x} gas at room temperature. - Highlights: • The Cu/Cu{sub x}O nanoarchitectures with hollow nanospheres are successfully synthesized. • The method is used for preparing the with Cu/Cu{sub x}O adjustable phase composition. • The C3 sample exhibites excellent gas-sensing propertie to NO{sub x} at room temperation. • The Cu/Cu{sub x}O nanoarchitectures have significant for application of gas sensor. - Abstract: The Cu/Cu{sub x}O nanoarchitectures with 30–70 nm hollow nanospheres are successfully synthesized by a facile wet chemical method. The synthesized products have been studied by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermo gravimetric-differential scanning calorimetry (TG-DSC) analysis. The Cu/Cu{sub x}O sensors based on the nanoarchitectures are used to detect the NO{sub x} at room temperature. The results demonstrate that the obtained Cu/Cu{sub x}O nanoarchitectures reduced by 3 mmol NaBH{sub 4} exhibits excellent gas-sensing properties: low detection limit of 0.97 ppm, relatively high sensitivity, short response time, broad linear range and high selectivity. The reasons for gas-sensing activity enhancement on Cu/Cu{sub x}O nanoarchitectures are discussed. The Cu/Cu{sub x}O nanocrystalline with the hierarchical pores structure and tunable compositions have significant for application of gas sensor.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Hydrothermal synthesis, characterization and luminescent properties of GdPO{sub 4}·H{sub 2}O:Tb{sup 3+} nanorods and nanobundles

Graphical abstract: - Highlights: • The GdPO{sub 4}·H{sub 2}O:Tb{sup 3+} nanocrystals have been synthesized via a hydrothermal method. • The formation mechanisms of the nanorods and nanobundles were put forward. • The luminescent intensities are associated with the morphologies and sizes. - Abstract: In this paper, the Tb{sup 3+}-doped GdPO{sub 4}·H{sub 2}O nanorods and nanobundles have been synthesized by the hydrothermal method with and without glycine, respectively. The X-ray powder diffraction (XRD), thermogravimetric and differential thermal analysis (TG–DTA), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), energy-dispersive spectra (EDS) and photoluminescence (PL) were employed to characterize the as-obtained products. It was found that the addition of glycine and the pH value have crucial influences on the formation of the resulting morphologies and sizes. The possible formation mechanisms for GdPO{sub 4}·H{sub 2}O:Tb{sup 3+} nanorods and nanobundles were put forward. A detailed investigation on the photoluminescence of GdPO{sub 4}·H{sub 2}O:Tb{sup 3+} different samples revealed that the luminescent properties of products are strongly correlated with the morphologies, sizes, coordination environment and crystal field symmetry.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Microstructure characterization and electrical transport of nanocrystalline ZrO{sub 2}–CeO{sub 2} solid solution

Graphical abstract: - Highlights: • Monoclinic ZrO{sub 2} phase has been changed to cubic ZrO{sub 2} phase within a short milling. • Conductivity increases due to change of phase from monoclinic to cubic. • A maximum has been observed in the s–T curve. • A transformation from −ve to +ve ac magnetoconductance has been observed. - Abstract: Nanocrystalline ZrO{sub 2}–CeO{sub 2} (ZC) solid solution is synthesized by high energy ball-milling the powder mixture of monoclinic (m) ZrO{sub 2}–10 mol% CeO{sub 2} in air medium. X-ray powder diffraction (XRD) patterns show that the method IS effective to synthesize cubic (c) ZrO{sub 2} phase within a short milling time. Formation mechanism, structural and microstructural changes of different phases and relative phase abundances have been estimated by Rietveld analysis of XRD patterns. The dc conductivity has been enhanced due to monoclinic to cubic phase transformation. A transformation from small polaron hopping to correlated barrier hoping has been observed from the of temperature dependence frequency exponent study. A crossover from negative to positive ac magnetoconductance has been observed at temperature T = 280 K and 230 K for unmilled (ZC0H) and 8 h (ZC8H) milled samples, respectively.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Synthesis of CdTe/TiO{sub 2} nanoparticles and their photocatalytic activity

Graphical abstract: - Highlights: • CdTe/TiO{sub 2} photocatalysts were synthesized through a facile and convenient method. • The photosensitized degradation of RhB was largely enhanced by the composite. • Products prepared under MBSL condition exhibited higher photocatalytic activities. • The effect of MBSL had been investigated. - Abstract: Visible-light-induced CdTe/TiO{sub 2} photocatalysts were synthesized under multibubble sonoluminescence (MBSL) condition. The morphology, phase and optical properties of the products have been characterized by X-ray powder diffraction, field emission scan electron microscope, UV–vis absorption spectroscopy and photoluminescence spectroscopy. The results showed that as-prepared nanoparticles are well-crystallized with a better size distribution. In addition, the photocatalytic activities of products were evaluated using the photocatalytic degradation of rhodamine B as a probe reaction. The results showed that the products synthesized under MBSL condition exhibited higher photocatalytic activities than those without MBSL irradiation.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Preparation, characterization and gas sensitivity of polypyrrole/γ-Fe{sub 2}O{sub 3} hybrid materials

Graphical abstract: - Highlights: • PPy/γ-Fe{sub 2}O{sub 3} hybrid materials were prepared by sol–gel polymerization in situ. • Different reactant molar ratios resulted in different microstructures of γ-Fe{sub 2}O{sub 3} and molecular weights of PPy. • PPy/γ-Fe{sub 2}O{sub 3} hybrids had selectivity for NH{sub 3} gases at low temperatures (<100 °C). • The sensing mechanism was suggested to be related to the existence of p–n heterojunctions in the PPy/γ-Fe{sub 2}O{sub 3} hybrid material. - Abstract: Polypyrrole (PPy)/γ-Fe{sub 2}O{sub 3} hybrid materials were prepared by sol–gel polymerization in situ and characterized by Fourier transform infrared (FT-IR), X-ray powder diffraction (XRD), thermogravimetric and differential thermal analysis (TG–DTA) and high-resolution transmission electron microscope (HRTEM). The gas sensitivities in CO, H{sub 2}, NH{sub 3}, ethanol or acetone atmospheres were determined at 30 °C, 60 °C and 90 °C. FT-IR and XRD patterns suggest that ferric oxide in the hybrids was γ-Fe{sub 2}O{sub 3}, with a diameter of approximately 5 nm. TG–DTA and HRTEM analyses showed that different reactant molar ratios of pyrrole monomer: Fe(NO{sub 3}){sub 3}·9H{sub 2}O resulted in different microstructures of γ-Fe{sub 2}O{sub 3} and molecular weights of PPy. An increased amount of Fe(NO{sub 3}){sub 3}·9H{sub 2}O increased the degree of uniformity of the molecular weight of PPy and resulted in a change of γ-Fe{sub 2}O{sub 3} microstructure from granular to stick particles. The results of gas sensitivities showed that the PPy/γ-Fe{sub 2}O{sub 3} hybrids exhibited high sensitivity to NH{sub 3} at mild operating temperature (<100 °C). Furthermore, the sensing mechanism was also discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2013

The AMWCNTs supported porous nanocarbon composites for high-performance supercapacitor

Graphical abstract: The AMWCNTs supported porous nanocarbon composites were prepared by a easy method. The composites had shown good performances for electrochemical energy storage with high specific capacitance and good stability. - Highlights: • The AMWCNTs supported porous nanocarbon composites were prepared. • The composites have good conductivity and large BET specific surface areas. • The composites had shown high specific capacitance, and good stability. - Abstract: The porous nanocarbons supported by acid-treated multiwall carbon nanotubes (PC@ACNTs) were prepared by the combination of the hydrothermal polymerization of glucose on ACNTs, carbonization under N{sub 2} protection and final activation with ZnCl{sub 2}. The materials were characterized by transmission electron microscopy, X-ray powder diffraction and Raman spectra. The results indicated that the ACNTs distributed uniformly into the framework of the porous carbon. The composites showed the high BET specific surface area up to 1712 m{sup 2} g{sup −1} and good conductivity. The electrochemical measurements indicated that the composites processed good performances for electrochemical energy storage (210 F g{sup −1} at 0.5 A g{sup −1}), and high stability (>99.9%), much higher than the corresponding ACNTs, porous carbons and the samples prepared by using raw MWCNTs as source. The good performance of PC@ACNTs composites was relative with the synergy of good conductivity of ACNTs and large specific surface areas of PC.

36 MATERIALS SCIENCE↗
DOE OSTI2013

One step synthesis of Bi@Bi{sub 2}O{sub 3}@carboxylate-rich carbon spheres with enhanced photocatalytic performance

Graphical abstract: Functional groups of sodium gluconate play synergetic roles in the formation of Bi@Bi{sub 2}O{sub 3}@carboxylate-rich carbon core–shell nanosturctures (Bi@Bi{sub 2}O{sub 3}@CRCSs). Bi@Bi{sub 2}O{sub 3}@CRCSs exhibits significant enhanced photocatalytic activity under visible light irradiation. - Highlights: • One step synthesis of Bi@Bi{sub 2}O{sub 3}@carboxylate-rich carbon spheres. • Functional groups of sodium gluconate play synergetic roles in the formation of Bi@Bi{sub 2}O{sub 3}@CRCSs. • Bi@Bi{sub 2}O{sub 3}@CRCSs exhibits enhanced photocatalytic activity under visible light irradiation. - Abstract: Bi@Bi{sub 2}O{sub 3}@carboxylate-rich carbon core-shell nanosturctures (Bi@Bi{sub 2}O{sub 3}@CRCSs) have been synthesized via a one-step method. The core–shell nanosturctures of the as-prepared samples were confirmed by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and Raman spectroscopy. The formation of Bi@Bi{sub 2}O{sub 3}@CRCSs core–shell nanosturctures should attribute to the synergetic roles of different functional groups of sodium gluconate. Bi@Bi{sub 2}O{sub 3}@CRCSs exhibits significant enhanced photocatalytic activity under visible light irradiation (λ > 420 nm) and shows an O{sub 2}-dependent feature. According to trapping experiments of radicals and holes, hydroxyl radicals were not the main active oxidative species in the photocatalytic degradation of MB, but O{sub 2}·{sup −} are the main active oxidative species.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Iron oxide hydroxide nanoflower assisted removal of arsenic from water

Graphical abstract: Non-magnetic polycrystalline iron oxide hydroxide nanoparticle with flower like morphology is found to play as an effective adsorbent media to remove As(III) from 300 μg L{sup −1} to less than 10 μg L{sup −1} from drinking water over wide range of pH. TEM image clearly reveals that the nanoparticle looks flower like morphology with average particle size less than 20 nm. The maximum sorption capacity of the sorbent is found to be 475 μg g{sup −1} for arsenic at room temperature and the data fitted to different isotherm models indicate the heterogeneity of the adsorbent surface. The material can be regenerated up to 70% using dilute hydrochloric acid and it would be utilized for de-arsenification purposes. - Highlights: • The work includes synthesis of iron oxide hydroxide nanoflower and its applicability for the removal of arsenic from water. • The nanoparticle was characterized using modern instrumental methods like FESEM, TEM, BET, XRD, etc. • The maximum sorption capacity of the sorbent is found to be 475 μg g{sup −1} for arsenic at room temperature. • The sorption is multilayered on the heterogeneous surface of the nano adsorbent. • The mechanism of arsenic removal of IOH nanoflower follows both adsorption and ion-exchange. - Abstract: Non-magnetic polycrystalline iron oxide hydroxide nanoparticle with flower like morphology is found to play as an effective adsorbent media to remove As(III) from 300 μg L{sup −1} to less than 10 μg L{sup −1} from drinking water over wide range of pH. The nanoparticle was characterized by X-ray powder diffraction analysis (XRD), BET surface area, FTIR, FESEM and TEM images. TEM image clearly reveals flower like morphology with average particle size less than 20 nm. The nanoflower morphology is also supported by FESEM images. The maximum sorption capacity of the sorbent is found to be 475 μg g{sup −1} for arsenic and the data fitted to different isotherm models indicate the heterogeneity of the adsorbent surface. Study on adsorption kinetics shows that adsorption of arsenic onto iron oxide hydroxide nanoflower follows pseudo-second order kinetic. The material can be regenerated up to 70% using dilute hydrochloric acid and it would be utilized for de-arsenification purposes.

36 MATERIALS SCIENCE↗