Study of the Affecting Factors on the Desulfurization Activities of Co-Doped TiO2 Photocatalyst

2014 ◽  
Vol 700 ◽  
pp. 152-155
Author(s):  
Shu Qin Wang ◽  
Zhi Ping Han ◽  
Yin Tao Wang

The different preparation conditions of TiO2and NV co-doped TiO2prepared by the sol-gel method were evaluated through the SO2photocatalysis removal efficiency and continuous utilization time under the visible light. Results showed that the SO2removal reactions included adsorption and photocatalytic oxidation which was obvious for the NV co-doped TiO2; its continuous utilization time and removal efficiency reached 420min and 98.76% which was higher than that of TiO2,N- TiO2and V- TiO2when the co-doping of N and V, the calcining temperature was 500 °C by 3h and pH was 3.5 with the microwave by 23min.The XPS and XRD analysis indicated that coexisting V4+and V5+,microwave drying, calcination temperature and mixture of anatase and rutile strongly affected the desulfurization photocatalytic activity of NV co-doped TiO2.

2011 ◽  
Vol 197-198 ◽  
pp. 891-894 ◽  
Author(s):  
Cheng Zhi Jiang ◽  
Xu Dong Lu

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.


2019 ◽  
Vol 97 (3) ◽  
pp. 227-232 ◽  
Author(s):  
Ye Zhao ◽  
Fan Tong ◽  
Mao Hua Wang

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 %.


2021 ◽  
Vol 11 (4) ◽  
pp. 12215-12226

Undoped, Cerium (Ce) doped, Manganese (Mn) doped and Ce-Mn co-doped Barium Titanate (BaTiO3) with the general formula Ba1-xCexMnyTi1-yO3 (where x = 0.00, 0.01, 0.02, 0.03, y = 0.00; x = 0.00, y =0.01, 0.02, 0.03; and x = y = 0.01, 0.02,0.03) were synthesized by solid-state reaction method and sintered at 1200 C for 4 hr with an aim to study their structural and electrical properties. The grain size of the samples has been estimated using the Scanning Electron Microscopy (SEM). The X-ray Diffraction (XRD) analysis indicates that the structure of the Ce-doped and Ce-Mn co-doped BaTiO3 is cubic. However, the undoped BaTiO3 and Mn-doped BaTiO3 confirmed the tetragonal-cubic mixed phases. With the change of doping concentrations, the positions of different peaks shifted slightly. The lattice parameter varied irregularly with increasing doping concentration because of Mn's changeable valency. EDX spectra confirmed the presence of Ba, Ti, Ce, and Mn contents in the co-doped samples with stoichiometric ratio. Crystallinity is observed to be clearly increased when Ce-Mn is co-doped in BaTiO3. J-V characteristic curves indicate transition from conducting to semiconducting nature for the doped and co-doped samples with the increase in temperature. The dielectric constant of the samples increases up to 4500 with the doping concentration. The higher values of dielectric constant are observed for the 2% Mn-doped and 1% Ce-Mn co-doped samples compared to the other undoped samples. For the undoped and Mn-doped samples, constant dielectric values increase with temperature but decrease for the Ce-doped and Ce-Mn co-doped samples. It is inferred that co-doping of BaTiO3 with Ce and Mn would be beneficial and economical for its applications.


2017 ◽  
Vol 31 (17) ◽  
pp. 1750195
Author(s):  
Li Zhang ◽  
Yibao Li ◽  
Zhen Tang ◽  
Yan Deng ◽  
Hui Yuan ◽  
...  

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.


2013 ◽  
Vol 774-776 ◽  
pp. 964-967
Author(s):  
Ping Cao ◽  
Yue Bai

Successful synthesis of Cu, Co co-doped ZnO film is obtained by sol-gel method. The structural and electrical properties of the sample were investigated. X-ray diffraction spectroscopy analyses indicate that the Co and Cu co-doping can not disturb the structure of ZnO. No additional peaks are observed in the Zn0.99Co0.01CuxO and Cu+ and Co2+ substitute for Zn2+ without changing the wurtzite structure. By Hall-effect measurement p-type conductivity was observed for the Cu co-doped film. XPS result confirmed Cu ions are univalent in the films.


2007 ◽  
Vol 336-338 ◽  
pp. 574-576
Author(s):  
Hua Rong ◽  
Chun Fang Ye ◽  
Yu Yang ◽  
Guo Dong Qian ◽  
Zhi Yu Wang ◽  
...  

Laser dyes perylene red (p-red) or pyrromethene 567 (p567) were co-doped with coumarin 440 (C440) or coumarin 500 (C500) into MTES- and VTES-derived organically modified silicates (ORMOSILs) by sol-gel process. The effects of coumarin dye concentration on the laser performances of p-red and p567 were investigated. The results from laser efficiency measurements illustrated that at optimized coumarin concentration, the slope efficiency of co-doped p-red increased by a factor of 2 while that of co-doped p567 increased marginally. It was also found that by co-doping coumarin, the laser wavelength of p-red blue shifted and the laser thresholds for p567 and p-red could be reduced. The energy transfer mechanisms involved were also discussed.


2007 ◽  
Vol 336-338 ◽  
pp. 91-94
Author(s):  
Wen Feng Zhang ◽  
Qing Zhi Yan ◽  
Xin Tai Su ◽  
Chang Chun Ge

The Nb and Co doped barium titanate was synthesized by sol-gel auto-ignition synthesis process (abbreviated SAS) and compared with the doped powder of the same composition prepared by conventional ball milling process. The phase structure, morphology of the two as-obtained powders and correlative dielectric properties of sintered BaTiO3-based ceramics were measured. The XRD analysis demonstrated that the SAS powder was the Ba(M0.047Ti0.953)O3(M=Nb, Co) solid solution based on BaTiO3; it further suggested that Nb and Co cations could replace the Ti ions and reach reciprocal balance of acceptors and donors during the decomposition step of the organic fuel by igniting the dried gel. TEM observation showed that the Ba(M0.047Ti0.953)O3(M=Nb, Co) particles were spherical with the size ranged from 30 to 110nm. Furthermore, it was found that the value of the Curie temperature of both the doped powders was being lowered in comparison with pure BaTiO3 (Tc≈128°C ); and the dielectric constant at room temperature of the SAS powder was 5840, which was much higher than that of the conventional ball milling doped powder(3013). It was attributed to the maximum homogeneous distribution of dopants in Ba-Ti initial solution at atomic level via the SAS process.


2014 ◽  
Vol 556-562 ◽  
pp. 429-432
Author(s):  
Ping Cao ◽  
Yue Bai ◽  
Zhi Qu

Successful synthesis of room-temperature ferromagnetic semiconductors, (Cu, Co) co-doped ZnO film is obtained by sol-gel method. It is found that the essential ingredient in achieving room-temperature ferromagnetism is Cu co-doping. By Hall-effect measurement ap-type conductivity was observed for the Cu co-doped films, which induced the room-temperature ferromagnetism.


2013 ◽  
Vol 781-784 ◽  
pp. 2237-2240 ◽  
Author(s):  
Benjamas Noophum ◽  
Lek Sikong ◽  
Kalayanee Kooptanond

The photocatalytic N-S co-doped TiO2films coated on glass fibers were successfully prepared by sol-gel, dip-coating and calcination methods. The effect of doping concentration on crystalline size, microstructure, morphology, optical property and photocatalytic activity was investigated. The films were characterized by XRD, SEM, EDS, UV-vis DRS and FT-IR. The photocatalytic activity was evaluated by the degradation of methylene blue (MB). N-S co-doping has an effect on light adsorption wavelength shifted to visible light region which can lower the band gap energy of N-S co-doped due to the replacement of O atom in TiO2by N and S atoms to form Ti-O-N and Ti-O-S structures. Thiourea, a source of nitrogen and sulfur could increase viscosity of sol used for coating on glass fibers, resulting in larger particles size and more surface roughness of the doped films.TiO2films with 5 mol% N-S co-doped showed an excellent photocatalytic performance under fluorescent light irradiation.


2018 ◽  
Vol 56 (1A) ◽  
pp. 219
Author(s):  
Dao Viet Thang

In this study, multiferroicMultiferroic Bi1-xYxFe0.975Ni0.025O3 (x = 0.00, 0.05, 0.10, and 0.15) called as (Y, Ni)                co-doped BiFeO3 materials were synthesized by a sol-gel method.  and characterized by X-ray diffraction diagrams and(XRD), energy-dispersive X-ray (EDX) and vibrating sample magnetization (VSM) measurements demonstrated. The result showed that Bi1-xYxFe0.975Ni0.025O3all investigated materials waspresent a single phase of the perovskite-type rhombohedral structure. Ferromagnetism and ferroelectricity of the Bi1-xYxFe0.975Ni0.025O3 materials have been investigated. Results showed that the co-doping by (Y, Ni) for (Bi, Fe)  have affected in enhancing by the (Y, Ni) co-doping, as a result the ferroelectric polarization and magnetization of BiFeO3. The magnetic characterization indicated that the ferromagnetic behavior wasthe initial BiFeO3 materialwere enhanced with increasing concentration of Y3+ for (Y, Ni) co-substituted of BiFeO3. Which could beion. It is attributed to the defferentdifference of the magnetic momentmoments of Ni2+ and Fe3+, and+ ions, as well as the Y3+-Fe3+,+ and Y3+-Ni2+ super-exchange interaction. Theinteractions. The characteristics of the investigated materials, such as remanent magnetization (Mr), saturation magnetization (Ms), remanent polarization (2Pr) and saturation polarization (2Ps) continuously increase upon increasing in the range of x from 0.00 to 0.15. When x = 0.15, the values of Mr and Ms are 0.078 and 0.794 emu/g, respectively. The values of 2Pr and 2Ps are 16.58 and 27.99 µC/cm2, respectively. Origin of ferromagnetic and ferroelectric properties of Bi1-xYxFe0.975Ni0.025O3 materials will be discussed in this paper.


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