scholarly journals Nano-sized SnO2 Photocatalysts: Synthesis, Characterization and Their Application for the Degradation of Methylene Blue Dye

2016 ◽  
Vol 8 (3) ◽  
pp. 399-411 ◽  
Author(s):  
M. T. Uddin ◽  
Y. Sultana ◽  
M. A. Islam
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Uv Light ◽  
Irradiation Time ◽  
Sno2 Nanoparticles ◽  
Average Crystallite Size ◽  
Precipitation Method ◽  
Catalyst Loading ◽  
Blue Dye ◽  
Effect Of Ph

In the present study, tin oxide (SnO2) nanoparticles were prepared by precipitation method using tin tetrachloride (SnCl4) as precursor and ammonia solution as precipitating agent followed by calcination at 400 ºC for 2 h. As-prepared SnO2 particles were characterized by X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR). The powder XRD results revealed that the SnO2 nanoparticles had a typical tetragonal rutile (cassiterite) structure and the average crystallite size calculated by using the Debye –Scherrer equation was found to be approximately 5.1 nm. The photocatalytic activity of the as-prepared photocatalysts was investigated by degrading methylene blue (MB) dye. The effect of pH, catalyst loading and initial dye concentration on photocatalytic degradation was investigated. Results showed that the SnO2 nanoparticles represented excellent photocatalytic activity for the degradation of MB under UV light with 200 min of irradiation time. The results also showed that the pH of solution had a direct influence on the photocatalysis process and basic pH was favorable for the degradation of MB. The effect of pH on photocatalytic activity was explained with the help of zero point charge (pHpzc). Furthermore, the photocatalysts could be easily recycled without significant change in the catalytic activity.

scholarly journals Synthesis and Characterization of CeO2-SiO2Nanoparticles by Microwave-Assisted Irradiation Method for Photocatalytic Oxidation of Methylene Blue Dye

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
R. M. Mohamed ◽  
E. S. Aazam
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Photocatalytic Oxidation ◽  
Uv Light ◽  
Irradiation Time ◽  
High Surface ◽  
Blue Dye ◽  
Methylene Blue Dye ◽  
Microwave Assisted ◽  
Small Pore

CeO2-SiO2nanoparticles were synthesized for the first time by a facile microwave-assisted irradiation process. The effect of irradiation time of microwave was studied. The materials were characterized by N2adsorption, XRD, UV-vis/DR, and TEM. All solids showed mesoporous textures with high surface areas, relatively small pore size diameters, and large pore volume. The X-ray diffraction results indicated that the as-synthesized nanoparticles exhibited cubic CeO2without impurities and amorphous silica. The transmission electron microscopy (TEM) images revealed that the particle size of CeO2-SiO2nanoparticles, which were prepared by microwave method for 30 min irradiation times, was around 8 nm. The photocatalytic activities were evaluated by the decomposition of methylene blue dye under UV light irradiations. The results showed that the irradiation under the microwave produced CeO2-SiO2nanoparticles, which have the best crystallinity under a shorter irradiation time. This indicates that the introduction of the microwave really can save energy and time with faster kinetics of crystallization. The sample prepared by 30 min microwave irradiation time exhibited the highest photocatalytic activity. The photocatalytic activity of CeO2-SiO2nanoparticles, which were prepared by 30 min irradiation times was found to have better performance than commercial reference P25.

scholarly journals Effect of Oxalic Acid Leaching on Photocatalytic Activity of Natural Sphalerite

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.

scholarly journals Synthesis, characterization and photocatalytic activity of Zn2+, Mn2+ and Co2+ doped SnO2 nanoparticles

2019 ◽  
Vol 9 (5) ◽  
pp. 4199-4204 ◽  
Author(s):  
Oeindrila Mukhopadhyay ◽  
Soumita Dhole ◽  
Badal Kumar Mandal ◽  
Fazlur-Rahman Nawaz Khan ◽  
Yong-Chien Ling
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Transition Metal ◽  
Band Gap ◽  
Sno2 Nanoparticles ◽  
Transition Metal Ions ◽  
Band Gap Energy ◽  
Blue Dye ◽  
Gap Energy ◽  
Sno2 Nps

Nanomaterials with many improved properties have been used in versatile applications. Herein we have synthesized SnO2 NPs doped with transition metal ions such as Zn2+, Mn2+ and Co2+ through a facile and inexpensive hydrothermal approach. The synthesized nanomaterials were characterized by XRD, FT-IR, SEM and UV-Vis analysis. The optical properties of the NPs were characterized by using UV–vis and photoluminescence spectroscopy (PLS). Their photocatalytic performances were investigated by degrading methylene blue (MB) dye with UV irradiation. Transition metal doping to SnO2 NPs improved the photocatalytic activity to degradation of methylene blue dye due to tuning of band gap energy i.e. lowering of band gap energy compared to undoped SnO2 NPs. The results suggest that the synthesized NPs could be used efficiently for remediation/degradation of environmentally hazardous dyes from waste water or environmental cleanup.

Enhanced Photocatalytic Activity by Silver-Modified Bismuth Vanadate

2017 ◽  
Vol 757 ◽  
pp. 88-92
Author(s):  
Cheewita Suwanchawalit ◽  
Kamonchanok Roongraung ◽  
Supat Buddee ◽  
Sumpun Wongnawa ◽  
Avinash Patil
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Visible Region ◽  
Bismuth Vanadate ◽  
Light Irradiation ◽  
Precipitation Method ◽  
Blue Dye ◽  
Vis Spectroscopy

Silver-modified bismuth vanadate (Ag-BiVO4) photocatalysts were easily prepared via the co-precipitation method. The effects of silver contents on the chemical properties of BiVO4 were evaluated. The prepared Ag-BiVO4 samples were characterized by several techniques such as X-ray diffractometry (XRD), scanning electron microscopy (SEM), and diffused reflectance UV-Vis spectroscopy (DRS). The mixed phase of monoclinic scheetlite structure and characteristic peaks of silver particles were found. Silver contents strongly affect the morphology of the prepared Ag-BiVO4 samples. DRS spectra revealed that the synthesized Ag-BiVO4 samples exhibited strong absorption in the visible region. The absorption in the visible zone is responsible for the high photocatalytic activity of Ag-BiVO4 under visible light irradiation. The photocatalytic degradation of methylene blue under visible light irradiation was studied using the BiVO4 as photocatalysts. The photocatalytic results reveal that the prepared Ag-BiVO4 samples could degrade the methylene blue dye.

Visible light assisted photocatalytic degradation of methylene blue dye and mixture of dyes using ZrO2-TiO2 nanocomposites

2020 ◽  
Vol 16 ◽  
Author(s):  
Radhakrishna S. Sutar ◽  
Rani P. Barkul ◽  
Meghshyam K. Patil
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Anatase Phase ◽  
Physicochemical Characterization ◽  
Catalytic Efficiency ◽  
Catalyst Loading ◽  
Blue Dye ◽  
Methylene Blue Dye

Background: Different photocatalysts such as TiO2, ZnO, WO3 have been used for degradation of organic pollutants. However, these materials having some limitations, which has been affected the catalytic efficiency in the various transformations. The composites of these materials with other oxide can produce better results by tuning structural as well as optoelectrical properties. The composite of TiO2 with ZrO2 has attracted attention due to their use in different areas as ZrO2 and TiO2 have similar physicochemical features. Methods: This research contain the preparation of ZrO2-TiO2 nanocomposites by hydrothermal method and analysis of photocatalytic activity for degradation of methylene blue and mixture of dyes under visible light irradiation. Results: Physicochemical characterization of ZrO2-TiO2 nanocomposites has been studied by using different techniques. Prepared catalysts has shown anatase phase of TiO2 and tetragonal phase of ZrO2. XRD, FESEM and HRTEM have supported the nanocrystalline nature of the composites. The photocatalytic activity of composites and bare TiO2 samples were demonstrated for the degradation of methylene blue dye. Enhanced activity has been shown by composite having Ti:Zr 3:1 molar proportion i.e., Ti3Zr. Effect of concentration of methylene blue, pH of solution, catalyst loading has been studied by using Ti3Zr. Also, degradation of mixture of three dyes namely methylene blue, rhodamine B and methyl orange has been studied. Conclusion: In summary, prepared zro2-tio2 composites found to be nanocrystalline and visible light active. these catalysts has shown activity for photocatalytic degradation of methylene blue and mixture of dyes.

scholarly journals Effect of calcination temperature, pH and catalyst loading on photodegradation efficiency of urea derived graphitic carbon nitride towards methylene blue dye solution

RSC Advances ◽  
2019 ◽  
Vol 9 (27) ◽  
pp. 15381-15391 ◽  
Author(s):  
Devina Rattan Paul ◽  
Rishabh Sharma ◽  
S. P. Nehra ◽  
Anshu Sharma
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Carbon Nitride ◽  
Dye Degradation ◽  
Synthesis Temperature ◽  
Catalyst Loading ◽  
Blue Dye ◽  
Methylene Blue Dye ◽  
Reaction Conditions ◽  
Photodegradation Efficiency

The appropriate synthesis temperature and optimized photodegradation reaction conditions result in an appreciable enhancement of the photocatalytic activity of urea derived innate g-C3N4 towards MB dye degradation.

scholarly journals Photocatalytic Degradation of Methylene Blue by Fe/ZnO/SiO2Nanoparticles under Visiblelight

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
R. M. Mohamed ◽  
I. A. Mkhalid ◽  
E. S. Baeissa ◽  
M. A. Al-Rayyani
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Visible Light Irradiation ◽  
Photocatalytic Oxidation ◽  
Catalyst Loading ◽  
Blue Dye ◽  
Methylene Blue Dye ◽  
Illumination Time

The photocatalytic activity of Fe/ZnO/SiO2catalysts under visible-light irradiation for the degradation of methylene blue was evaluated. The effect of pH, illumination time, amount of catalyst loaded, and initial dye concentration on the degradation efficiency of methylene blue was investigated. The results reveal that the optimum photocatalytic oxidation conditions of methylene blue are as follows:pH=4and illumination time is 30 min, the amount of catalyst loading is 0.075 g/L and 50 ppm methylene blue dye concentration. Under these conditions, the removal efficiency of methylene blue was 100%.

Physical Properties of Fe3+/TiO2 Nanoparticles and Photocatalytic Disinfection of Foodborne Microorganisms

2018 ◽  
Vol 17 (3) ◽  
pp. 312-321
Author(s):  
Long Men ◽  
Zhan Ge ◽  
Sun Meng-Yun ◽  
Zhuang Hong ◽  
Wang Ran
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Physical Properties ◽  
Salmonella Typhimurium ◽  
Uv Light ◽  
Meat Products ◽  
Blue Dye ◽  
Methylene Blue Dye ◽  
Photocatalytic Disinfection

In this article, we studied the preparation of Fe3+/TiO2 nanoparticles and the photocatalytic disinfection effects of two typical foodborne microorganisms, a gram-negative bacterium (Salmonella typhimurium) and a gram-positive bacterium (Listeria monocytogenes), in meat products. The physical properties of Fe3+/TiO2 nanoparticles embedded with various levels of Fe3+ (0%–10%) and synthesized through an impregnation process were investigated using X-ray diffraction, transmission electron microscopy, and UV-vis spectrophotometer, and their photocatalytic activities were evaluated by measuring the degradation of methylene blue dye and the disinfection of foodborne pathogens S. typhimurium and L. monocytogenes under visible light and UV light. Fe3+ ions were found to be scattered across TiO2 surfaces or across TiO2 crystal lattices as microcrystals. However, the capacity for TiO2 nanoparticles to absorb visible light was significantly enhanced after they were embedded with.Fe3+/TiO2 nanoparticles with molar ratios (R) of Fe3+ to TiO2 of 0.001:1, 0.005:1, and 0.01:1 exhibited higher levels of methylene blue dye photocatalytic degradation and higher levels of foodborne pathogen photocatalytic disinfection than the TiO2 control. However, nanoparticles containing >1% Fe3+ exhibited lower levels of photocatalytic activity than the TiO2 control. Salmonella typhimurium was more resistant to the nano-Fe3+/TiO2 treatment than L. monocytogenes under visible and UV light conditions. These experiments demonstrate that embedding Fe3+ in TiO2 nanoparticles does not remarkably influence the TiO2 nanoparticle size or structure. Embedding appropriate levels of Fe3+ content (0.1%–1%) can enhance the photocatalytic activity of TiO2 nanoparticles.

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