Influence of Ag Photodeposition Conditions over SERS Intensity of Ag/ZnO Microspheres for Nanomolar Detection of Methylene Blue

Surface enhanced Raman spectroscopy (SERS) is considered a versatile and multifunctional technique with the ability to detect molecules of different species at very low molar concentration. In this work, hierarchical ZnO microspheres (ZnO MSs) and Ag/ZnO MSs were fabricated and decorated by hydrothermal and photodeposition methods, respectively. For Ag deposition, precursor molar concentration (1.9 and 9.8 mM) and UV irradiation time (5, 15, and 30 min) were evaluated by SEM, TEM, X-ray diffraction and Raman spectroscopy. X-ray diffraction showed a peak at 37.9° corresponding to the (111) plane of Ag, whose intensity increases as precursor concentration and UV irradiation time increases. SEM images confirmed the formation of ZnO MSs (from 2.5 to 4.5 µm) building by radially aligned two-dimensional ZnO nanosheets with thicknesses below 30 nm. The Raman spectra of Ag/ZnO MSs exhibited a vibration mode at 486 cm−1 which can be directly associated to Ag deposition on ZnO MSs surface. The performance of SERS substrate was evaluated using rhodamine 6G. The SERS substrate grown at 9.8 mM during 30 min showed the best SERS activity and the ability to detect methylene blue at 10−9 M.

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High efficient photocatalytic activity of Zn-Al-Ti layered double hydroxides nanocomposite

MATEC Web of Conferences ◽

10.1051/matecconf/201814901087 ◽

2018 ◽

Vol 149 ◽

pp. 01087 ◽

Cited By ~ 1

Author(s):

F. Amor ◽

A. Diouri ◽

I. Ellouzi ◽

F. Ouanji ◽

M. Kacimi

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Uv Irradiation ◽

Layered Double Hydroxides ◽

Removal Rate ◽

X Ray Diffraction ◽

Simple Method ◽

X Ray ◽

High Efficient ◽

Double Hydroxides

This work establishes a simple method for synthesising layered double hydroxides (LDHs) powders with coprecipitation. The characteristics of the samples were investigated y X-ray diffraction (XRD), scanning electron microscopy (SEM) and spectrophotometer UV–Vis (DRS). Non-uniform distribution was shown for LDHs samples by SEM. Photocatalytic efficiencies were tested using methylene blue (MB) dye as a model contaminant under UV irradiation. In particular, Zn–Al-Ti LDH exhibited an excellent performance towards MB degradation compared with commercial TiO2 nanoparticles. Methylene blue removal percentage was reached at almost 100%, whereas commercial TiO2 reached a removal rate of only 66% under the same conditions within 20 min. The aim of the current work is to prepare Zn-Al-Ti layered double hydroxides nanocomposite and to evaluate their photocatalytic activity in the removal of methylene blue under UV irradiation.

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Effect of Oxalic Acid Leaching on Photocatalytic Activity of Natural Sphalerite

10.21203/rs.3.rs-117664/v1 ◽

2020 ◽

Author(s):

Chukwunonso Onyenanu ◽

Lovet Emembolu

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Visible Light ◽

Irradiation Time ◽

Acid Leaching ◽

Blue Dye ◽

Light Illumination ◽

X Ray Diffraction ◽

X Ray ◽

Visible Light Illumination

Abstract Photocatalytic activity of the natural semiconducting sphalerite mineral from Abuni, Nasarawa State, Nigeria was studied for the degradation of methylene blue (MB). Natural Sphalerite as a visible – light responsive photocatalyst was characterized by X ray diffraction (XRD), X ray fluorescence (XRF) and surface area analysis. To further enhance the photocatalytic activity of natural Sphalerite, the chemical composition of the sphalerite was varied via leaching with oxalic acids. The photocatalytic activity of the Natural sphalerite, leached sphalerite and as well as the calcined leachates was tested for MB degradation under visible light illumination. The result shows a very high percentage of MB degradation by natural sphalerite after 60mintues of light irradiation time. A composite of ZnO -α –Fe2O3 -ϒ-Fe2O3 with traces amount of MoO and MnO2 was synthesized by calcination of the obtained leachates at 1000°C for 4hours. The photocatalytic degradation of methylene blue dye follows pseudo first order kinetics.

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Synthesis of TiO2-NiFe2O4 nanocomposites using coprecipitation method as photocatalyst for methylene blue removal

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/882/1/012022 ◽

2021 ◽

Vol 882 (1) ◽

pp. 012022

Author(s):

A Hardian ◽

Devikha ◽

S Budiman ◽

T Yuliana ◽

H Sujono ◽

...

Keyword(s):

Methylene Blue ◽

Textile Industry ◽

Irradiation Time ◽

Average Crystallite Size ◽

Coprecipitation Method ◽

X Ray Diffraction ◽

X Ray ◽

Adsorption Performance ◽

Methylene Blue Removal ◽

Ferrite Spinel

Abstract Methylene blue, a basic dye that is important in the coloring process in the textile industry. However, the use of the dye Methylene blue is hazardous for the skin, the eyes, and swallowed. Three composition types of TiO2-NiFe2O4 nanocomposites (75:25, 50:50, and 25:75) had been synthesized using a simple coprecipitation method. The photodegradation and adsorption performance of the nanocomposites were also evaluated. Based on X-ray diffraction analysis, both the titania anatase and nickel ferrite spinel phases appeared in each nanocomposite’s diffraction pattern. The average crystallite size of the nanocomposites was 38 nm, 33 nm, and 41 nm for compositions 75:25, 50:50, and 25:75, respectively. The optimum photodegradation activity of TiO2-NiFe2O4 nanocomposites was achieved at composition 75:25 %mol with >99% methylene blue degraded during 120 minutes of UV irradiation time. However, all nanocomposites also have adsorption capability toward methylene blue with an optimum percentage of 98%. Therefore, TiO2-NiFe2O4 nanocomposites can be used either as photocatalysts or adsorbents for methylene blue removal in an aqueous solution.

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Decolorization of Methylene Blue withTiO2Sol via UV Irradiation Photocatalytic Degradation

International Journal of Photoenergy ◽

10.1155/2010/643182 ◽

2010 ◽

Vol 2010 ◽

pp. 1-6 ◽

Cited By ~ 48

Author(s):

Jun Yao ◽

Chaoxia Wang

Keyword(s):

Methylene Blue ◽

Uv Irradiation ◽

Anatase Phase ◽

High Photocatalytic Activity ◽

X Ray Diffraction ◽

Initial Concentration ◽

X Ray ◽

Photodegradation Efficiency ◽

Degradation Ratio ◽

Catalyst Load

TiO2sol was prepared for the degradation of methylene blue (MB) solution under ultraviolet (UV) irradiation. The absorption spectra of MB indicated that the maximum wavelength, 663 nm, almost kept the same. The performance of 92.3% for color removal was reached after 160 min. The particle size ofTiO2sol was about 22.5 nm. X-ray diffraction showed thatTiO2consisted of a single anatase phase. The small size and anatase phase probably resulted in high photocatalytic activity ofTiO2sol. The degradation ratio decreased as the initial concentration of MB increased. The photodegradation efficiency decreased in the order ofpH 2>pH 9>pH 7. Regarding catalyst load, the degradation increased with the mass of catalyst up to an amount of 1.5 g⋅L−1then decreased as the mass continued to increase. The addition ofH2O2toTiO2sol resulted in an increase on the degradation ratio.

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Raman spectroscopy and X-ray diffraction of lithium niobate at temperatures up to 1300○-4.80pt○C

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2005126021 ◽

2005 ◽

Vol 126 ◽

pp. 101-105 ◽

Cited By ~ 1

Author(s):

B. Moulin ◽

L. Hennet ◽

D. Thiaudière ◽

P. Melin ◽

P. Simon

Keyword(s):

Raman Spectroscopy ◽

Lithium Niobate ◽

X Ray Diffraction ◽

X Ray

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Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue

Polymers ◽

10.3390/polym13040558 ◽

2021 ◽

Vol 13 (4) ◽

pp. 558

Author(s):

Wenhui Zhu ◽

Caiyun Zhang ◽

Yali Chen ◽

Qiliang Deng

Keyword(s):

Methylene Blue ◽

Photoelectron Spectroscopy ◽

Room Temperature ◽

Degradation Rate ◽

Model Compound ◽

Vibrating Sample Magnetometer ◽

Simulated Sunlight ◽

X Ray Diffraction ◽

X Ray ◽

Ft Ir

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

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Structural and Raman Vibrational Studies ofCeO2-Bi2O3Oxide System

Advances in Materials Science and Engineering ◽

10.1155/2009/502437 ◽

2009 ◽

Vol 2009 ◽

pp. 1-4 ◽

Cited By ~ 8

Author(s):

L. Bourja ◽

B. Bakiz ◽

A. Benlhachemi ◽

M. Ezahri ◽

J. C. Valmalette ◽

...

Keyword(s):

Solid Solution ◽

Raman Spectroscopy ◽

Phase Changes ◽

Phase System ◽

X Ray Diffraction ◽

X Ray ◽

Vibrational Studies ◽

Coprecipitation Route

A series of ceramics samples belonging to theCeO2-Bi2O3phase system have been prepared via a coprecipitation route. The crystallized phases were obtained by heating the solid precursors at600∘Cfor 6 hours, then quenching the samples. X-ray diffraction analyses show that forx<0.20a solid solutionCe1−xBixO2−x/2with fluorine structure is formed. For x ranging between 0.25 and 0.7, a tetragonalβ′phase coexisting with the FCC solid solution is observed. For x ranging between 0.8 and 0.9, a new tetragonalβphase appears. Theβ′phase is postulated to be a superstructure of theβphase. Finally, close tox=1, the classical monoclinicα Bi2O3structure is observed. Raman spectroscopy confirms the existence of the phase changes as x varies between 0 and 1.

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