Facile Synthesis and Characterization of Spinel NiFe2O4 Nanoparticles and Studies of Their Photocatalytic Activity for Oxidation of Alcohols

In this paper, we report a novel and facile approach for the synthesis of spinel NiFe2O4 nanoparticles and studies of its photocatalytic activity for oxidation of alcohols. The as-synthesized catalyst was thoroughly characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), elemental mapping, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption isotherm (BET) analysis. The TEM image reveals cubic shapes with an average particle size of 10–20 nm. The as-synthesized spinel NiFe2O4 has proved to be an excellent photocatalyst for oxidation of alcohol to the aldehyde with a conversion of 80% and selectivity of 99%. The catalyst has also proved to be noteworthy as it does not loss its catalytic activity even after five cycles of reuse.

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Multiferroic Bismuth Ferrite Nanoparticles: Rapid Sintering Synthesis, Characterization, and Optical Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.152-153.81 ◽

2010 ◽

Vol 152-153 ◽

pp. 81-85

Author(s):

Xiong Wang ◽

Yin Lin ◽

Jin Guo Jiang

Keyword(s):

Electron Microscopy ◽

Phase Transition ◽

Optical Properties ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Average Particle Size ◽

Average Particle ◽

X Ray ◽

Bifeo3 Nanoparticles ◽

Rapid Sintering

The homogeneous multiferroic BiFeO3 nanoparticles with average particle size of 85 nm have been successfully synthesized by a simple sol-gel route. The prepared sample was characterized by a variety of techniques, such as X-ray diffractometry, thermogravimetric analysis and differential thermal analysis, differential scanning calorimeter analysis, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The obtained results shows that rapid sintering and subsequently quenching to room temperature are the two vital important factors for the preparation of pure BiFeO3. The magnetic phase transition (TN = 369 °C) and the ferroelectric phase transition (TC = 824.5 °C) were determined, revealing the antiferromagnetic and ferroelectric nature of the as-prepared BiFeO3 nanoparticles. The optical properties of the nanopowders were investigated. The strong band-gap absorption at 486 nm (2.55 eV) of the BiFeO3 nanoparticles may bring some novel applications.

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CdS Loaded Activated Carbon: An Efficient, Solar Light Driven Photocatalyst for RhB Dye Degradation

Oriental Journal Of Chemistry ◽

10.13005/ojc/350316 ◽

2019 ◽

Vol 35 (3) ◽

pp. 1037-1044

Author(s):

Sagar Kande ◽

Udhav Ghoshir ◽

Jayshree Khedkar ◽

Anil Gambhire

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Activated Carbon ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Dye Degradation ◽

Xrd Analysis ◽

Band Gap Energy ◽

X Ray ◽

Adsorption Desorption

A series of novel photocatalyst with CdS loaded on activated carbon (xAC/CdS) were successfully synthesized by a simple hydrothermal method. The activated carbon content was varied between 0-7 wt. %. The prepared photocatalysts were characterized by X-ray diffraction, scanning electron microscopy with EDX, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-Vis diffuse reflectance spectroscopy, N2 adsorption-desorption analysis and photoluminescence spectroscopy. The photocatalytic activity of as-synthesized photocatalysts was studied for RhB dye degradation under natural sunlight irradiation. XRD analysis assigned both cubic and hexagonal morphology for xAC/CdS photocatalysts. The UV-vis DRS studies showed that loading of CdS on activated carbon enhances its visible light absorption with decrease in band gap energy. The lowest photoinduced e/h pair recombination rate in 3wt% AC/CdS results in optimum photocatalytic activity as revealed by photoluminescence study. The enhancement in dye degradation ability (̴ 11 times) of prepared photocatalysts can be attributed to synergistic effect of CdS and activated carbon.

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Hierarchical Porous Batio3 Nano-Hexagons as A Visible Light Photocatalyst

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.5.20022 ◽

2018 ◽

Vol 7 (4.5) ◽

pp. 105 ◽

Cited By ~ 2

Author(s):

Harsha Bantawal ◽

D Krishna Bhat

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Visible Light ◽

Photoelectron Spectroscopy ◽

X Rays ◽

Hydrothermal Route ◽

Visible Light Photocatalyst ◽

X Ray ◽

Hierarchical Porous ◽

Bet Analysis

Hierarchical porous BaTiO3 nano-hexagons was synthesized via a simple hydrothermal route by using TiO2 and Ba(OH)2.8H2O as starting materials under alkaline environment and its photocatalytic activity was evaluated under visible light by taking methylene blue (MB) as a model pollutant. The prepared BaTiO3 was characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), energy dispersive X-rays analysis (EDX), high resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET) analysis and diffused reflectance spectroscopy (DRS) techniques. It is noteworthy that the BaTiO3 nano-hexagons exhibited significant photocatalytic activity towards the degradation of MB under visible light irradiation. This significant photocatalytic activity of BaTiO3 under visible light is mainly attributed to the special morphology and formation of Ti3+ defects.

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Synthesis and Characterization of Pyrochlore Bi2Sn2O7Doping with Praseodymium by Hydrothermal Method and Its Photocatalytic Activity Study

International Journal of Photoenergy ◽

10.1155/2013/234806 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Weicheng Xu ◽

Guangyin Zhou ◽

Jianzhang Fang ◽

Zhang Liu ◽

YunFang Chen ◽

...

Keyword(s):

Photocatalytic Activity ◽

Electron Microscope ◽

Visible Light ◽

Hydrothermal Method ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

X Ray ◽

Transmission Electron ◽

20 Nm ◽

Adsorption Desorption

Praseodymium doped Bi2Sn2O7(BSO), as a visible-light responsive photocatalyst, was prepared by a hydrothermal method with different dopant contents. The as-prepared photocatalysts were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), N2adsorption-desorption isotherm, X-ray photoelectron spectroscopy analysis (XPS), and UV-Vis diffuse reflectance spectroscopy (DRS). The photocatalytic activity of prepared catalysts was evaluated by the degradation of Rhodamine Bextra (RhB) and 2,4-dichlorophenol (2,4-DCP) in aqueous solution under visible light irradiation. It was found that Pr doping inhibited the growth of crystalline size and the as-prepared materials were small in size (10–20 nm). In our experiments, Pr-doped BSO samples exhibited enhanced visible-light photocatalytic activity compared to the undoped BSO, and the optimal dopant amount of Pr was 1.0 mol% for the best photocatalytic activity. On the basis of the calculated PL spectra, the mechanism of enhanced photocatalytic activity has been discussed.

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Enhanced Photocatalytic Activity of CuWO4 Doped TiO2 Photocatalyst Towards Carbamazepine Removal under UV Irradiation

Separations ◽

10.3390/separations8030025 ◽

2021 ◽

Vol 8 (3) ◽

pp. 25

Author(s):

Chukwuka Bethel Anucha ◽

Ilknur Altin ◽

Emin Bacaksız ◽

Tayfur Kucukomeroglu ◽

Masho Hilawie Belay ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

Pure Tio2 ◽

Component Part ◽

Energy Yield ◽

Mechanical Agitation ◽

X Ray

Abatement of contaminants of emerging concerns (CECs) in water sources has been widely studied employing TiO2 based heterogeneous photocatalysis. However, low quantum energy yield among other limitations of titania has led to its modification with other semiconductor materials for improved photocatalytic activity. In this work, a 0.05 wt.% CuWO4 over TiO2 was prepared as a powder composite. Each component part synthesized via the sol-gel method for TiO2, and CuWO4 by co-precipitation assisted hydrothermal method from precursor salts, underwent gentle mechanical agitation. Homogenization of the nanopowder precursors was performed by zirconia ball milling for 2 h. The final material was obtained after annealing at 500 °C for 3.5 h. Structural and morphological characterization of the synthesized material has been achieved employing X-ray diffraction (XRD), Fourier transform infra-red (FTIR) spectroscopy, Brunauer–Emmett–Teller (BET) N2 adsorption–desorption analysis, Scanning electron microscopy-coupled Energy dispersive X-ray spectroscopy (SEM-EDS), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV-Vis diffuse reflectance spectroscopy (UV-vis DRS) for optical characterization. The 0.05 wt.% CuWO4-TiO2 catalyst was investigated for its photocatalytic activity over carbamazepine (CBZ), achieving a degradation of almost 100% after 2 h irradiation. A comparison with pure TiO2 prepared under those same conditions was made. The effect of pH, chemical scavengers, H2O2 as well as contaminant ion effects (anions, cations), and humic acid (HA) was investigated, and their related influences on the photocatalyst efficiency towards CBZ degradation highlighted accordingly.

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Study of the Effect of TiO2 Layer on the Adsorption and Photocatalytic Activity of TiO2-MoS2 Heterostructures under Visible-Infrared Light

International Journal of Photoenergy ◽

10.1155/2020/8740825 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

N. Cruz-González ◽

O. Calzadilla ◽

J. Roque ◽

F. Chalé-Lara ◽

J. K. Olarte ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Nitrogen Adsorption ◽

High Photocatalytic Activity ◽

Infrared Light ◽

Polluted Water ◽

Light Spectrum ◽

X Ray

In the last decade, the urgent need to environmental protection has promoted the development of new materials with potential applications to remediate air and polluted water. In this work, the effect of the TiO2 thin layer over MoS2 material in photocatalytic activity is reported. We prepared different heterostructures, using a combination of electrospinning, solvothermal, and spin-coating techniques. The properties of the samples were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms, UV-Vis diffuse reflectance spectroscopy (UV-Vis-DRS), and X-ray photoelectron spectroscopy (XPS). The adsorption and photocatalytic activity were evaluated by discoloration of rhodamine B solution. The TiO2-MoS2/TiO2 heterostructure presented three optical absorption edges at 1.3 eV, 2.28 eV, and 3.23 eV. The high adsorption capacity of MoS2 was eliminated with the addition of TiO2 thin film. The samples show high photocatalytic activity in the visible-IR light spectrum.

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Study on Synthesis and Photocatalytic Activity of Porous Titania Nanotubes

Advances in Materials Science and Engineering ◽

10.1155/2016/3532817 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Huang Liu ◽

Yanhua Zhang ◽

Hongtao Yang ◽

Wei Xiao ◽

Lanlan Sun

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Filter Paper ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Cellulose Nanofibers ◽

Titania Nanotubes ◽

Tetrabutyl Titanate ◽

X Ray ◽

Porous Titania

Using the common natural cellulose substance (filter paper) and triblock copolymer (Pluronic P123) micelles as dual templates, porous titania nanotubes with enhanced photocatalytic activity have been successfully synthesized through sol-gel methods. Firstly, P123 micelles were adsorbed onto the surfaces of cellulose nanofibers of filter paper, followed by hydrolysis and condensation of tetrabutyl titanate around these micelles to form titania layer. After calcination to remove the organic templates, hierarchical titania nanotubes with pores in the walls were obtained. The sample was characterized by X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption/desorption, Fourier Transform Infrared Spectroscopy (FT-IR), Ultraviolet-Visible Diffuse Reflectance Spectroscopy (UV-Vis DRS), and X-ray photoelectron spectroscopy (XPS). As compared with commercial P25 catalyst, the porous titania nanotubes prepared by this method displayed significantly enhanced photocatalytic activity for degrading methyl orange under UV irradiation. Within 10 minutes, the porous titania nanotubes are able to degrade over 70% of the original MO, while the value for the commercial Degussa P25 is only about 33%.

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Nanocrystalline α-Fe2O3: A Superparamagnetic Material for w-LED Application and Waste Water Treatment

10.21203/rs.3.rs-327620/v1 ◽

2021 ◽

Author(s):

Mahesh Gaidhane ◽

Deepak Taikar ◽

Pravin Gaidhane ◽

Kalpana Nagde

Keyword(s):

Photocatalytic Activity ◽

Waste Water Treatment ◽

Sol Gel ◽

Average Particle Size ◽

Emission Spectra ◽

Broad Emission Band ◽

Average Particle ◽

X Ray ◽

Prepared Material ◽

Cie Chromaticity

Abstract Nanocrystalline α-Fe2O3 is synthesized by sol-gel technique. The prepared nanomaterial was characterized by X-ray diffraction (XRD), SEM, TEM, Fourier Transform Infrared (FTIR) spectroscopy, Vibrating Sample Magnetometry (VSM) and photoluminescence (PL) techniques. X-ray powder diffraction analysis confirmed the formation of α-Fe2O3. Electron microscopy showed spherical morphologies with an average particle size of 30-40 nm. The magnetic property of the prepared material was studied by VSM at room temperature. VSM study shows superparamagnetic nature of the synthesized nanoparticles. Photoluminescence (PL) emission spectra show intense broad emission band centered at 570 nm with 393 nm excitation indicating its usefulness for w-LED application. The CIE-chromaticity color coordinates of prepared material were calculated. The photocatalytic activity of the α-Fe2O3 nanoparticles was analyzed and the nanopowder exhibited good photocatalytic activity for the removal AO7 from its aqueous solution.

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Synthesis of cuprous oxide nanocubes combined with chitosan nanoparticles and its application to p-nitrophenol degradation

Mongolian Journal of Chemistry ◽

10.5564/mjc.v22i48.1564 ◽

2021 ◽

Vol 22 (48) ◽

Author(s):

Tran Thi Bich Quyen ◽

Ngo Nguyen Tra My ◽

Do Thi Thuy Ngan ◽

Duy Toan Pham ◽

Doan Van Hong Thien

Keyword(s):

Photocatalytic Activity ◽

Cuprous Oxide ◽

Treatment Time ◽

Average Particle Size ◽

Chitosan Nanoparticles ◽

Synthetic Approach ◽

Average Particle ◽

X Ray ◽

Nitrophenol Reduction ◽

Nitrophenol Degradation

For the first time, cuprous oxide nanocubes (Cu2O NCBs) were successfully combined with chitosan nanoparticles (CS NPs) to generate Cu2O NCBs/CS NPs composites material with highly optical property and photocatalytic activity using a simple and eco-friendly synthetic approach at room temperature for 30 min. The synthesized Cu2O NCBs NPs/CS NPs were determined characterizations by Ultraviolet-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), X – ray Diffraction (XRD), Transmission Electron Microscope (TEM) and Energy-dispersive X-ray spectroscopy (EDX). Results show that the Cu2O NCBs/CS NPs composites have an average particle size of ~3-5 nm; in which, Cu2O has the form of nanocubes (Cu2O NCBs) with size ~3-4 nm and chitosan nanoparticles with spherical shape (CS NPs) with size ~4-5 nm. In addition, the percent (%) composition of elements present in Cu2O NCBs/CS NPs composites material have been obtained respective: Cu (23.99%), O (38.18%), and C (33.61%). Moreover, Cu2O NCBs/CS NPs composites material was also investigated for photocatalytic activity applied in p-nitrophenol degradation. The obtained results showed that the catalytic capability of Cu2O NCBs/CS NPs for p-nitrophenol reduction reached the highest efficiency >55% in the treatment time of 25 min, and this efficiency was higher than that result of using ZnO@chitosan nanoparticles (ZnO@CS NPs) catalyst under the same conditions for comparison.

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Ni/MWCNT-Supported Palladium Nanoparticles as Magnetic Catalysts for Selective Oxidation of Benzyl Alcohol

Australian Journal of Chemistry ◽

10.1071/ch12484 ◽

2013 ◽

Vol 66 (5) ◽

pp. 564 ◽

Cited By ~ 15

Author(s):

Mingmei Zhang ◽

Qian Sun ◽

Zaoxue Yan ◽

Junjie Jing ◽

Wei Wei ◽

...

Keyword(s):

Electron Microscopy ◽

Benzyl Alcohol ◽

Bimetallic Nanoparticles ◽

Average Particle Size ◽

Average Particle ◽

X Ray ◽

Oxidation Of Benzyl Alcohol ◽

Uniform Dispersion ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

Well dispersed Pd@Ni bimetallic nanoparticles on multi-walled carbon nanotubes (Pd@Ni/MWCNT) are prepared and used as catalysts for the oxidation of benzyl alcohol. Scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy analysis, and X-ray diffraction were performed to characterise the synthesised catalyst. The results show a uniform dispersion of Pd@Ni nanoparticles on MWCNT with an average particle size of 4.0 nm. The as synthesised catalyst was applied to the oxidation of benzyl alcohol. A 99 % conversion of benzyl alcohol and a 98 % selectivity of benzaldehyde were achieved by using the Pd@Ni/MWCNT (Pd: 0.2 mmol) catalyst with water as a solvent and H2O2 as oxidant at 80°C. The catalytic activity of Pd@Ni/MWCNT towards benzyl alcohol is higher than that of a Pd/MWCNT catalyst at the same Pd loadings. The catalyst can be easily separated due to its magnetic properties.

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