The Preparation, Characterization, and Photocatalytic Activities of Co-TiO2

2011 ◽  
Vol 239-242 ◽  
pp. 39-43
Author(s):  
Ying Na Xie ◽  
Zheng De Wang
Keyword(s):  
Methyl Orange ◽  
Uv Light ◽  
Sol Gel ◽  
Degradation Process ◽  
Rutile Phase ◽  
Tem Analysis ◽  
Co Doping ◽  
Ion Doping ◽  
Titanium Tetra Isopropoxide ◽  
Co Doped

Photocatalytic degradation of methyl orange in water was examined using Co-doped TiO2 nanoparticles. These photocatalysts were synthesized by a sol–gel method from titanium tetra-isopropoxide with different concentrations of Co(III) dopant and calcination temperature at 600°C. The samples were characterized by XRD, DRS, TEM analysis. The XRD results showed that the anatase-to-rutile phase transformation was greatly inhibited by Co ion doping. The increase of Co doping enhanced “red-shift” in the UV-vis absorption spectra. The TEM images confirmed the dopants suppressed the growth of TiO2 grains. The photocatalytic activity of the nanoparticles under UV light was investigated by measuring the photodegradation of methyl orange solutions. Parameters affecting photocatalytic process such as the dosage of catalyst, dopant and methyl orange concentrations were investigated. The degradation process was optimized using a Co concentration of 1.0 mol%, 30mg Co-doped TiO2 and MO concentration of 10mg/L.

Synthesis, characterization, and photocatalytic activity of silver and zinc co-doped TiO2 nanoparticle for photodegradation of methyl orange dye in aqueous solution

2019 ◽  
Vol 97 (9) ◽  
pp. 642-650 ◽  
Author(s):  
Gabriel O. Oladipo ◽  
Akinola K. Akinlabi ◽  
Samson O. Alayande ◽  
Titus A.M. Msagati ◽  
Hlengilizwe H. Nyoni ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Pore Size ◽  
Average Pore Size ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Rutile Phase ◽  
Absorption Bands ◽  
Average Pore ◽  
Methyl Orange Dye ◽  
Co Doped

In this study, TiO2 nanocrystals, 1 mol% Ag-doped TiO2, and 1 mol% Ag and 0.6 mol% Zn co-doped TiO2 powders were synthesized by the sol–gel route. Their photocatalytic activities on methyl orange dye under visible irradiation were investigated. The powders were characterized by X-ray diffraction (XRD), UV–visible spectroscopy (UV–vis), Brunauer–Emmett–Teller (BET), and Fourier transform infrared spectroscopy (FTIR). The XRD results revealed the presence of a rutile phase with an average crystallite size of 9 and 11 nm. The UV–vis spectra showed a red-shift towards a longer wavelength with the corresponding decrease in band gap from 2.9 to 2.5 eV. The BET surface areas of the nanoparticles ranged from 4.7 to 11.8 m2 g−1 with an average pore size between 18.9 and 56.6 nm. The Ag-doped TiO2 has the largest surface area of 11.8 m2 g−1, whereas the Ag–Zn co-doped TiO2 was found to have the highest pore size and volume. The absorption bands at 750–500 cm−1 were attributed to the –O–Ti–O– bond in the TiO2 lattice. The photocatalytic efficiency was highest at an optimum pH of 4.1 for Ag–Zn co-doped TiO2. The results confirmed that Ag-doped and Ag–Zn co-doped TiO2 were more effective than pure TiO2. The kinetic data were fitted into a pseudo first-order equation using a Langmuir–Hinshelwood kinetic model.

Sol-Gel Preparation, Characterization and Photocatalytic Activity of Co Doped Nano-TiO2

2010 ◽  
Vol 177 ◽  
pp. 54-57 ◽  
Author(s):  
Li Na Meng ◽  
Wen Yuan Xu ◽  
Ting Xu
Keyword(s):  
Thin Films ◽  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Sol Gel ◽  
Inhibitory Effect ◽  
Pure Tio2 ◽  
Tio2 Thin Films ◽  
Doped Tio2 ◽  
Co Doping ◽  
Co Doped

Co doped TiO2 nanoparticles and thin films were prepared from Ti(OC4H9)4 by sol-gel method. The influence of Co-doping and its content on the crystallite structure and phase composition of TiO2 was systematically investigated by SEM and XRD, the precursor was analysed by TGA. The photocatalytic activity of nanocomposites was investigated in the photocatalytic degradation of methyl orange. The results indicated that the inhibitory effect of Co-doping on the phase transformation of TiO2 from anatase to rutile receded obviously when the calcination temperature was changed to 650°C from 550°C. Under the ultraviolet light radiation, the favourite Co-doping concentration was 1% and the obtained Co doped TiO2 thin films exhibited higher photocatalytic activity than nanoparticles and pure TiO2 in the photodegradation of methyl orange.

Role of Sm3+ Doping on Structural, Optical and Photoluminescence Properties of ZnO Nanoparticles Synthesized by Sol-gel Auto- combustion Method

2020 ◽  
Vol 5 (3) ◽  
pp. 236-251
Author(s):  
Eshwara I. Naik ◽  
Halehatty S.B. Naik ◽  
Ranganaik Viswanath
Keyword(s):  
Zno Nanoparticles ◽  
Sol Gel ◽  
Combustion Method ◽  
Content Increase ◽  
Photoluminescence Properties ◽  
Tem Analysis ◽  
Auto Combustion ◽  
Ion Doping ◽  
Doped Zno ◽  
Pl Intensity

Background: Various interesting consequences are reported on structural, optical, and photoluminescence properties of Zn1-xSmxO (x=0, 0.01, 0.03 and 0.05) nanoparticles synthesized by sol-gel auto-combustion route. Objective: This study aimed to examine the effects of Sm3+-doping on structural and photoluminescence properties of ZnO nanoparticles. Methods: Zn1-xSmxO (x=0, 0.01, 0.03 and 0.05) nanoparticles were synthesized by sol-gel auto combustion method. Results: XRD patterns confirmed the Sm3+ ion substitution through the undisturbed wurtzite structure of ZnO. The crystallite size was decreased from 24.33 to 18.46 nm with Sm3+ doping. The hexagonal and spherical morphology of nanoparticles was confirmed by TEM analysis. UV-visible studies showed that Sm3+ ion doping improved the visible light absorption capacity of Sm3+ iondoped ZnO nanoparticles. PL spectra of Sm3+ ion-doped ZnO nanoparticles showed an orange-red emission peak corresponding to 4G5/2→6HJ (J=7/2, 9/2 and 11/2) transition of Sm3+ ion. Sm3+ ion-induced PL was proposed with a substantial increase in PL intensity with a blue shift in peak upon Sm3+ content increase. Conclusion: Absorption peaks associated with doped ZnO nanoparticles were moved to a longer wavelength side compared to ZnO, with bandgap declines when Sm3+ ions concentration was increased. PL studies concluded that ZnO emission properties could be tuned in the red region along with the existence of blue peaks upon Sm3+ ion doping, which also results in enhancing the PL intensity. These latest properties related to Sm3+ ion-doped nanoparticles prepared by a cost-efficient process appear to be interesting in the field of optoelectronic applications, which makes them a prominent candidate in the form of red light-emitting diodes.

Synergistic Effect of Eu3+ and Sm3+ Co-Doping on Photocatalytic Activity of TiO2 Nanoparticles

2011 ◽  
Vol 197-198 ◽  
pp. 891-894 ◽  
Author(s):  
Cheng Zhi Jiang ◽  
Xu Dong Lu
Keyword(s):  
Photocatalytic Activity ◽  
Synergistic Effect ◽  
Sol Gel ◽  
Blue Shift ◽  
Nano Particles ◽  
Absorption Profile ◽  
Co Doping ◽  
The Matrix ◽  
Co Doped ◽  
The Eu

Pure TiO2, Eu3+and Sm3+co-doping TiO2composite nanoparticles have been prepared by sol-gel method and characterized by the techniques such as XRD, SEM and DRS. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a probe reaction to evaluate their photocatalytic activity. The matrix distortion of TiO2nano-particles increases after co-doping of Eu3+and Sm3+and a blue-shift of the absorption profile are clearly observed. The results show that co-doping of Eu3+and Sm3+inhibits the phase transformation of TiO2from anatase to rutile, decreases the diameter of TiO2nano-particles and significantly enhance the photocatalytic activity of TiO2. The Eu3+and Sm3+co-doped into TiO2nano-particles exert a synergistic effect on their photocatalytic activity.

Effect of cobalt doping on microstructures and dielectric properties of ZnO

2019 ◽  
Vol 97 (3) ◽  
pp. 227-232 ◽  
Author(s):  
Ye Zhao ◽  
Fan Tong ◽  
Mao Hua Wang
Keyword(s):  
Zno Nanoparticles ◽  
Sol Gel ◽  
Hexagonal Wurtzite Structure ◽  
Sem Analysis ◽  
Co Doping ◽  
In Doping ◽  
Zno Powders ◽  
Doped Zno ◽  
Zno Crystal ◽  
Co Doped

Pure and cobalt-doped ZnO nanoparticles (2.5, 5, 7.5, and 10 atom % Co) are synthesized by sol–gel method. The as-synthesized nanoparticles are characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FE-SEM) analysis. The nanoparticles of 0, 2.5, and 5 atom % Co-doped ZnO exhibited hexagonal wurtzite structure and have no other phases. Moreover, the (101) diffraction peaks position of Co-doped ZnO shift toward a smaller value of diffraction angle compared with pure ZnO powders. The results confirm that Co ions were well incorporated into ZnO crystal lattice. Simultaneously, Co doping also inhibited the growth of particles, and the crystallite size decreased from 43.11 nm to 36.63 nm with the increase in doping concentration from 0 to 10 atom %. The values of the optical band gap of all Co-doped ZnO nanoparticles gradually decreased from 3.09 eV to 2.66 eV with increasing Co content. Particular, the dielectric constant of all Co-doped ZnO ceramics gradually increased from 1.62 × 103 to 20.52 × 103, and the dielectric loss decreased from 2.36 to 1.28 when Co content increased from 0 to 10 atom %.

scholarly journals Preparation of Titanium Dioxide Nanoparticles Immobilized on Polyacrylonitrile Nanofibres for the Photodegradation of Methyl Orange

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Pardon Nyamukamba ◽  
Omobola Okoh ◽  
Lilian Tichagwa ◽  
Corinne Greyling
Keyword(s):  
Electron Microscopy ◽  
Titanium Dioxide ◽  
Methyl Orange ◽  
Organic Contaminants ◽  
Uv Light ◽  
Titanium Dioxide Nanoparticles ◽  
Xrd Analysis ◽  
Rutile Phase ◽  
Electrospinning Technique ◽  
Carbon Nanofibres

Herein, we describe the synthesis of titanium dioxide (TiO2) nanoparticles by the hydrolysis and condensation of titanium tetrachloride. The resulting nanoparticles were immobilized on polyacrylonitrile (PAN) based nanofibres by an electrospinning technique in order to allow simple isolation and reuse of titania semiconductor photocatalyst. The composite nanofibres were heat treated to convert the polymer nanofibres to carbon nanofibres and to convert amorphous TiO2to crystalline TiO2. X-ray diffraction (XRD) analysis showed that the rutile phase was the major phase and the equatorial peaks of PAN disappeared after heat treatment at 600°C. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analysis confirmed that some TiO2nanoparticles were encapsulated whereas some were surface residing on the electrospun nanofibres. The TiO2nanoparticles were found to lower the cyclization temperature of PAN as indicated by differential scanning colorimetry (DSC) and differential thermal analysis (DTA). Photocatalytic studies on the degradation of methyl orange dye under UV light irradiation showed that composite nanofibres were capable of degrading organic contaminants in water. The carbon nanofibres with surface residing titanium dioxide nanoparticles (TiO2/CNF-SR) showed the highest photocatalytic activity (59.35% after 210 minutes) due to direct contact between the TiO2photocatalyst and methyl orange.

Study on Photocatalytic Properties of Anatase Phase TiO2 Synthesized by Ultrasonic-Assisted Hydrolysis

2012 ◽  
Vol 573-574 ◽  
pp. 110-114 ◽  
Author(s):  
Jin Xia ◽  
Ri Ya Jin ◽  
Kai Xuan Guo ◽  
Si Jing Yang
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Uv Light ◽  
Anatase Phase ◽  
Ultrasonic Method ◽  
X Ray Diffraction ◽  
Hydrolysis Method ◽  
Titanium Tetra Isopropoxide ◽  
Ultrasonic Assisted ◽  
Ft Ir

Titanium dioxide powders were synthesized by ultrasonic-assisted hydrolysis reaction of titanium tetra-isopropoxide at the low-temperature. The samples were characterized by Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD). The photocatalytic activity of samples were investigated by the degradation of methyl orange under UV light radiation (6W, λ= 352nm) at room temperature. The results indicated that the products were mainly composed of high homogeneity anatase phases, and the methyl orange degradation rate can reach more than 90% under ultraviolet irradiation 180min. The photocatalytic activity of the samples prepared by ultrasonic method is higher than that of the samples prepared by conventional hydrolysis method.

Formation of Cobalt Doped Zinc Oxide Photocatalyst for Methyl Orange Degradation

2017 ◽  
Vol 264 ◽  
pp. 211-214 ◽  
Author(s):  
Farah Iddayu Abu Bakar ◽  
Katerina Anak Birang ◽  
Mohd Azam Mohd Adnan ◽  
Jeefferie Abd Razak ◽  
Syahriza Ismail
Keyword(s):  
Zinc Oxide ◽  
Methyl Orange ◽  
Sol Gel ◽  
Morphological Observation ◽  
X Ray Diffraction ◽  
Methyl Orange Degradation ◽  
Zno Nanostructure ◽  
Dopant Level ◽  
And Performance ◽  
Co Doped

The formation of cobalt (Co) doped zinc oxide (ZnO) as photocatalyst for photodegradation of methyl orange dye was investigated. The ZnO photocatalyst was produced with different concentration of Co by using sol gel method. The hexagonal wurtzite and zincite structure were successfully formed through this method. The morphological observation of nanorod and nanodisk structure formed was done by Field Emission Scanning Electron Microscope (FESEM). While, the structural properties of Co doped ZnO were identified by X-ray Diffraction (XRD) and Raman spectroscopy. The degradation performance of methyl orange was assessed and performance of photocatalytic activity was correlated to the amount of dopant level and oxygen vacancy of photocatalyst. There is an optimum amount of Co that can be doped into ZnO nanostructure in order to provide better degradation of methyl orange.

Effect of Co-Doped La3+/Halogen on Visible Light Photocatalytic Activity of TiO2

2011 ◽  
Vol 239-242 ◽  
pp. 1923-1928
Author(s):  
Qian Lin Chen ◽  
Yuan Wang ◽  
Chun Yan Zhong ◽  
Yu Guo
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Visible Light ◽  
Surface Area ◽  
Visible Light Photocatalytic Activity ◽  
Co Doping ◽  
Hydrolysis Method ◽  
Degradation Ratio ◽  
Co Doped ◽  
Visible Light Photocatalytic

La3+/halogen (F-, Cl-and Br-) co-doped TiO2was synthesized by alkoxide hydrolysis method. The prepared La3+/halogen TiO2photocatalysts with anatase phases and rutile phases were characterized with XRD, EDS, TEM and surface area analytic technology. Methyl orange was used as model pollutants to evaluate its visible light photocatalytic activity. The results showed that the co-doping of La3+and halogen ions improved the surface area of TiO2. Compared with 450°C and 650°C, La3+/Cl-and La3+/Br-co-doped TiO2calcined at 550°C exhibited much higher photocatalytic activity. The optimal doping ratio of La3+/F-, La3+/Cl-and La3+/Br-was 0.4, 0.6, and 0.5 ((wt%)/(wt%)), respectively. Moreover, the degradation ratio of methyl orange on La3+/halogen co-doped TiO2with the optimal ratio were all higher than the maximum degradation ratio on La3+, F-, Cl-and Br-doped TiO2prepared by the same method.

Magnetic and electrical transport properties of Sr2Ti1−xCoxO4 ceramics by sol–gel

2017 ◽  
Vol 31 (17) ◽  
pp. 1750195
Author(s):  
Li Zhang ◽  
Yibao Li ◽  
Zhen Tang ◽  
Yan Deng ◽  
Hui Yuan ◽  
...  
Keyword(s):  
Transport Properties ◽  
Electrical Transport ◽  
Low Temperatures ◽  
Sol Gel ◽  
Variable Range Hopping ◽  
Electrical Transport Properties ◽  
Co Doping ◽  
Hopping Model ◽  
Variable Range Hopping Model ◽  
Co Doped

Microstructures, electrical transport and magnetic properties of Sr[Formula: see text]Ti[Formula: see text]Co[Formula: see text]O[Formula: see text] ceramics are investigated. With Co doping, the Sr[Formula: see text]Ti[Formula: see text]Co[Formula: see text]O[Formula: see text] ceramics remain tetragonal structure while the grain size is decreased with doping. Magnetic moment is enhanced with Co doping and ferromagnetism is observed at low temperatures for Co-doped Sr[Formula: see text]TiO[Formula: see text]. The Sr[Formula: see text]Ti[Formula: see text]Co[Formula: see text]O[Formula: see text] and Sr[Formula: see text]Ti[Formula: see text]Co[Formula: see text]O[Formula: see text] show semiconductor-like transport properties, which can be well fitted by Mott variable range hopping model. The results will provide an effective route to synthesize Sr[Formula: see text]Ti[Formula: see text]Co[Formula: see text]O[Formula: see text] ceramics as well as to investigate the physical properties.

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