Efficient Removal of Cr(VI) with Fe/Mn Mixed Metal Oxide Nanocomposites Synthesized by a Grinding Method

Fe/Mn mixed metal oxides were synthesized facilely by a grinding method and were characterized by TEM, XRD, XPS, and BET. The characterization results revealed that mixed metal oxides were mainly composed of not highly crystallized Fe2O3and Mn3O4nanoparticles with a diameter about 3–5 nm. The specific BET surface areas of the composite were affected by the amounts of KCl diluent in the preparation process and about 268 m2/g of the composite can be achieved. Compared with metal oxide adsorbents existent, the composites showed good adsorption capacity, stability, and regeneration activity for Cr(VI) removal. The enhanced adsorption capacity was speculated to be ascribed to the synergistic effect of the mixed metal oxides. By monitoring the valence change in the adsorption process using XPS characterization, the mechanism for Cr(VI) removal on the composites was found to be a combination of electrostatic attraction and ion exchange. The above results demonstrated that the synthesized metal oxides nanocomposite is of great potential for Cr(VI) removal in the fields of remediation of environmental problems.

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Systematic study of TiO2/ZnO mixed metal oxides for CO2 photoreduction

RSC Advances ◽

10.1039/c9ra03435h ◽

2019 ◽

Vol 9 (38) ◽

pp. 21660-21666 ◽

Cited By ~ 2

Author(s):

Warren A. Thompson ◽

Alberto Olivo ◽

Danny Zanardo ◽

Giuseppe Cruciani ◽

Federica Menegazzo ◽

...

Keyword(s):

Design Of Experiments ◽

Metal Oxide ◽

Metal Oxides ◽

Systematic Study ◽

Mixture Design ◽

Mixed Metal Oxide ◽

Mixed Metal Oxides ◽

Systematic Design ◽

Co2 Photoreduction ◽

Mixed Metal

A novel example using a systematic design of experiments mixture design for developing mixed metal oxide photocatalysts for CO2 photoreduction.

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The pseudo-capacitive deionization behaviour of CuAl-mixed metal oxides

Environmental Science Water Research & Technology ◽

10.1039/c9ew00669a ◽

2020 ◽

Vol 6 (2) ◽

pp. 296-302 ◽

Cited By ~ 2

Author(s):

Wen Xi ◽

Haibo Li

Keyword(s):

Metal Oxide ◽

Metal Oxides ◽

Chloride Ions ◽

Mixed Metal Oxide ◽

Mixed Metal Oxides ◽

Capacitive Deionization ◽

Mixed Metal

In this work, a laminated CuAl-mixed metal oxide (CuAl-LDO) has been prepared and proposed as an electrode to interact with chloride ions for pseudo-capacitive deionization (P-CDI).

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Mixed Metal Oxide Mesoporous Nanoparticles For Environmental Remediation

Kongunadu Research Journal ◽

10.26524/krj303 ◽

2019 ◽

Vol 6 (2) ◽

pp. 61-65

Author(s):

Nithya Davis ◽

Usha Rajalakshmi P ◽

Sakthivel T

Keyword(s):

Metal Oxide ◽

Metal Oxides ◽

Environmental Remediation ◽

Oxide System ◽

Mixed Metal Oxide ◽

Blue Dye ◽

Ammonium Bromide ◽

Mixed Metal Oxides ◽

Structure Directing Agent ◽

Mixed Metal

Mesoporous mixed metal oxides (SnO2(x) -TiO2 (1-x) , x= 0.75,0.50 and 0.25) were synthesized by evaporation induced self assembly using cationic surfactant, Cetyl Trimethyl Ammonium Bromide (CTAB) as the structure directing agent. The small angle X-ray diffraction pattern of mesoporous SnO2 and SnO2-TiO2 mixed metal oxides revealed the presence of well defined mesostructure in the metal oxides. The mixed metal oxide system has crystallized in orthorhombic structure, resembling the host lattice. Mesopore channels were collapsed upon calcinations at 550°C. The optical absorption of the SnO2 has been extended into the visibleregion upon incorporation of “Ti”. A remarkable enhancement of the photocatalytic degradation efficiency (60% ) of (SnO2(0.5) -TiO2 (0.5) was observed against aqueous solution of methylene blue dye.

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Graphene oxide/mixed metal oxide hybrid materials for enhanced adsorption desulfurization of liquid hydrocarbon fuels

Fuel ◽

10.1016/j.fuel.2016.04.125 ◽

2016 ◽

Vol 181 ◽

pp. 531-536 ◽

Cited By ~ 41

Author(s):

Robert Menzel ◽

Diana Iruretagoyena ◽

Yifan Wang ◽

Salem M. Bawaked ◽

Mohamed Mokhtar ◽

...

Keyword(s):

Graphene Oxide ◽

Metal Oxide ◽

Hybrid Materials ◽

Liquid Hydrocarbon ◽

Hydrocarbon Fuels ◽

Mixed Metal Oxide ◽

Mixed Metal ◽

Adsorption Desulfurization ◽

Enhanced Adsorption

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The Key Role of Active Sites in the Development of Selective Metal Oxide Sensor Materials

Sensors ◽

10.3390/s21072554 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2554

Author(s):

Artem Marikutsa ◽

Marina Rumyantseva ◽

Elizaveta A. Konstantinova ◽

Alexander Gaskov

Keyword(s):

Metal Oxide ◽

Metal Oxides ◽

Active Sites ◽

Noble Metals ◽

Material Composition ◽

Mixed Metal Oxides ◽

Mixed Metal ◽

Sensor Materials ◽

The Impact

Development of sensor materials based on metal oxide semiconductors (MOS) for selective gas sensors is challenging for the tasks of air quality monitoring, early fire detection, gas leaks search, breath analysis, etc. An extensive range of sensor materials has been elaborated, but no consistent guidelines can be found for choosing a material composition targeting the selective detection of specific gases. Fundamental relations between material composition and sensing behavior have not been unambiguously established. In the present review, we summarize our recent works on the research of active sites and gas sensing behavior of n-type semiconductor metal oxides with different composition (simple oxides ZnO, In2O3, SnO2, WO3; mixed-metal oxides BaSnO3, Bi2WO6), and functionalized by catalytic noble metals (Ru, Pd, Au). The materials were variously characterized. The composition, metal-oxygen bonding, microstructure, active sites, sensing behavior, and interaction routes with gases (CO, NH3, SO2, VOC, NO2) were examined. The key role of active sites in determining the selectivity of sensor materials is substantiated. It was shown that the metal-oxygen bond energy of the MOS correlates with the surface acidity and the concentration of surface oxygen species and oxygen vacancies, which control the adsorption and redox conversion of analyte gas molecules. The effects of cations in mixed-metal oxides on the sensitivity and selectivity of BaSnO3 and Bi2WO6 to SO2 and VOCs, respectively, are rationalized. The determining role of catalytic noble metals in oxidation of reducing analyte gases and the impact of acid sites of MOS to gas adsorption are demonstrated.

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Enhanced adsorption of Congo red dye by functionalized carbon nanotube/mixed metal oxides nanocomposites derived from layered double hydroxide precursor

Chemical Engineering Journal ◽

10.1016/j.cej.2015.04.049 ◽

2015 ◽

Vol 275 ◽

pp. 315-321 ◽

Cited By ~ 90

Author(s):

Shuangxia Yang ◽

Lianying Wang ◽

Xiaodong Zhang ◽

Wenjun Yang ◽

Guilin Song

Keyword(s):

Carbon Nanotube ◽

Metal Oxides ◽

Layered Double Hydroxide ◽

Congo Red ◽

Mixed Metal Oxides ◽

Mixed Metal ◽

Congo Red Dye ◽

Enhanced Adsorption ◽

Red Dye ◽

Double Hydroxide

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Mixed Metal Oxide Synthesis by Thermolyses of Simple Heteropolymetallic Precursors in Oxygen

MRS Proceedings ◽

10.1557/proc-249-87 ◽

1991 ◽

Vol 249 ◽

Cited By ~ 3

Author(s):

Geoffrey Davies ◽

Bill C. Giessen ◽

Hui-Li Shao

Keyword(s):

Metal Oxide ◽

Metal Oxides ◽

Large Family ◽

Molecular Target ◽

Mixed Metal Oxide ◽

Aprotic Solvents ◽

Mixed Metal ◽

Highly Dispersed

ABSTRACTStepwise transmetalation of the neutral molecular target (µ4-O)N4 Cu4 C16(N is a monodentate pyridine) with M(NS)n transmealators (NS is a monanionic S-methyl hydrazinecarbodithioate ligand, M is Co (n = 2 or 3), Ni or Zn (n = 2)) in aprotic solvents gives a large family of heteropolymetallic products (µ4 - O)N4 (Co,Ni,Cu,Zn)4 C16 that contain from one to four different metals. Thermolysis of these solid products in flowing O2 at 220 - 250°C gives uniform, highly dispersed mixtures of the respective metal oxides. For example, thermolysis of bulk precursor (µ4 -O)N4 CoNiCuZnCl6 gives a uniform mixture of 1 - 2° particles of Co3 O4, NiO, CuO and ZnO.

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Preparation, Characterization and Application on Catalytic Removal of NOx for Ni/Cu/Fe Mixed Metal Oxides

Materials Science Forum ◽

10.4028/www.scientific.net/msf.953.172 ◽

2019 ◽

Vol 953 ◽

pp. 172-178

Author(s):

Hong Bo Liu ◽

Zhi Yong Huang

Keyword(s):

Metal Oxides ◽

Homogeneous Distribution ◽

Mixed Metal Oxides ◽

Mixed Metal ◽

Catalytic Activities ◽

Surface Areas ◽

Ft Ir ◽

Composition Structure ◽

Catalytic Removal ◽

Double Hydroxides

Ni/Cu/Fe mixed metal oxides (Ni/Cu/Fe-MMOs) were prepared by calcination of Ni/Cu/Fe layered double hydroxides (Ni/Cu/Fe-LDHs) precursors. Their composition, structure and morphology were characterized by ICP, XRD, FT-IR, BET and SEM. Ni/Cu/Fe-MMOs were used for catalytic removal of NOx by hydrocarbon. Their catalytic activities were studied by NOx analyzer. The results show that Ni/Cu/Fe-MMOs have homogeneous distribution of hexagon with particles size around 30~50nm and specific surface areas of 10~35 m2∙g–1. Ni/Cu/Fe-MMOs sample with molar ration of Ni/Cu/Fe = 5:1:3 exhibits the highest NOx conversion of 15.3%. Ni/Co/Cu/Fe-MMOs have better catalytic activities than both Ni/Cu/Fe-MMOs and Cu/Co/Fe-MMOs. For Ni/Cu/Fe-MMOs, propene is the better reductant than octane.

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