scholarly journals Mechanism of nitrogen-fluoride co-doped TiO2/bentonite composites removing tetracycline: A study in the co-doping ratio

2020 ◽  
Vol 26 (6) ◽  
pp. 200440-0
Author(s):  
Teng WANG ◽  
Zhaofu MENG ◽  
Xinxin WANG ◽  
Amjad ALI ◽  
Xuewen CAO ◽  
...  
Keyword(s):  
Molar Ratio ◽  
Composite Surface ◽  
Oh Groups ◽  
Doped Tio2 ◽  
Co Doping ◽  
Before And After ◽  
N Doping ◽  
Ft Ir ◽  
Doping Ratio ◽  
Co Doped

N-doped and N-F co-doped TiO2/bentonite composites were synthesized via the gel-sol method. The morphology, structure and surface charge of the composite before and after adsorption were used to determine the effect N/F doping ratio on TC removal. The results showed that, compared with undoped samples, the TC adsorption on N doped composites was reduced by 24.44% on average. N-F co-doping significantly increased the TC adsorption when the Ti-N-F molar ratio was 1:1: 0.01, reaching a maximum TC adsorption of 64.00 mmol·kg<sup>-1</sup>. The coverage of the N doped TiO2 increases as the N doping ratio increases; the specific surface area increased by 2.03 % on average, but the number of surface negative charges decreased by 36.24 % on average. FT-IR results confirmed that N doping reduced the number of -OH groups on the N-doped composites. Additionally, fluorination of N-F co-doped TiO2 and bentonite surfaces inhibits hydrogen bonding and π-π interactions between the TC and the composites. As the N doping ratio increased, the coverage of N-F co-doped TiO2 on the composite surface increased, resulting in the TC adsorption decrease with the increases N doping ratio.

Synthesis of Mg2+ and Al3+ Co-Doped Li3V2(PO4)3/C Powder

2012 ◽  
Vol 624 ◽  
pp. 204-207
Author(s):  
Qian Yang ◽  
Lei Zhang ◽  
Yan Gai Liu ◽  
Zhao Hui Huang ◽  
Ming Hao Fang
Keyword(s):  
Crystal Structure ◽  
Grain Size ◽  
Sol Gel ◽  
Gel Method ◽  
Sol Gel Method ◽  
Co Doping ◽  
Before And After ◽  
Ft Ir ◽  
Ir Analysis ◽  
Co Doped

Mg2+2+,Al3+ Co-doped Li3V2(PO4)3/C powder was synthesized by sol-gel method under nitrogen. The crystal structure and micrograph ofLi3V2(PO4)3/C powder before and after doping was investigated by XRD, SEM and FT-IR. The effect of Mg2+/Al3+ Co-doping onLi3V2(PO4)3/C powder was discussed. The results indicated that Mg2+2+,Al3+ Co-doping did not change the crystal structure of Li3V2(PO4)3, but decreased the grain size of the as-synthesized powder. The FT-IR analysis indicated that weak Al-O bond was generated after doping.

scholarly journals Green Synthesis of N/Zr Co-Doped TiO2 for Photocatalytic Degradation of p-Nitrophenol in Wastewater

Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 235
Author(s):  
Hayette Benkhennouche-Bouchene ◽  
Julien G. Mahy ◽  
Cédric Wolfs ◽  
Bénédicte Vertruyen ◽  
Dirk Poelman ◽  
...  
Keyword(s):  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Sol Gel ◽  
Visible Region ◽  
Chemical Properties ◽  
Pure Tio2 ◽  
Molar Ratio ◽  
Xps Spectra ◽  
Doped Tio2 ◽  
Co Doped

TiO2 prepared by a green aqueous sol–gel peptization process is co-doped with nitrogen and zirconium to improve and extend its photoactivity to the visible region. Two nitrogen precursors are used: urea and triethylamine; zirconium (IV) tert-butoxide is added as a source of zirconia. The N/Ti molar ratio is fixed regardless of the chosen nitrogen precursor while the quantity of zirconia is set to 0.7, 1.4, 2, or 2.8 mol%. The performance and physico-chemical properties of these materials are compared with the commercial Evonik P25 photocatalyst. For all doped and co-doped samples, TiO2 nanoparticles of 4 to 8 nm of size are formed of anatase-brookite phases, with a specific surface area between 125 and 280 m2 g−1 vs. 50 m2 g−1 for the commercial P25 photocatalyst. X-ray photoelectron (XPS) measurements show that nitrogen is incorporated into the TiO2 materials through Ti-O-N bonds allowing light absorption in the visible region. The XPS spectra of the Zr-(co)doped powders show the presence of TiO2-ZrO2 mixed oxide materials. Under visible light, the best co-doped sample gives a degradation of p-nitrophenol (PNP) equal to 70% instead of 25% with pure TiO2 and 10% with P25 under the same conditions. Similarly, the photocatalytic activity improved under UV/visible reaching 95% with the best sample compared to 50% with pure TiO2. This study suggests that N/Zr co-doped TiO2 nanoparticles can be produced in a safe and energy-efficient way while being markedly more active than state-of-the-art photocatalytic materials under visible light.

scholarly journals Photo-activity and low resistivity in N/Nb Co-doped TiO2 thin films by combinatorial AACVD

2016 ◽  
Vol 4 (2) ◽  
pp. 407-415 ◽  
Author(s):  
Nicholas P. Chadwick ◽  
Emily N. K. Glover ◽  
Sanjayan Sathasivam ◽  
Sulaiman N. Basahel ◽  
Shaeel A. Althabaiti ◽  
...  
Keyword(s):  
Thin Films ◽  
Functional Properties ◽  
Tio2 Thin Films ◽  
Doped Tio2 ◽  
Low Resistivity ◽  
Co Doping ◽  
Co Doped

Combinatorial AACVD has achieved the production of various niobium/nitrogen co-doped TiO2 materials in a single film. The co-doping concentrations have been correlated with functional properties.

scholarly journals In situ synthesis of ordered mesoporous Co-doped TiO2 and its enhanced photocatalytic activity and selectivity for the reduction of CO2

2015 ◽  
Vol 3 (18) ◽  
pp. 9491-9501 ◽  
Author(s):  
Tao Wang ◽  
Xianguang Meng ◽  
Guigao Liu ◽  
Kun Chang ◽  
Peng Li ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Energy Band ◽  
In Situ Synthesis ◽  
Molar Ratio ◽  
Doped Tio2 ◽  
Ordered Mesoporous ◽  
Reduction Of Co2 ◽  
Co Doped

The photocatalytic selectivity is improved by optimizing the energy-band configurations of Co-doped TiO2 through varying the molar ratio of Co/Ti.

scholarly journals Visible Light Responsive Nickel and Sulphur Co-Doped TiO2 Mesoporous Nanomaterial for the Degradation of Orange-II Dye and Antibacterial Activity on Escherichia coli

2018 ◽  
Vol 4 (5) ◽  
pp. 555-559
Author(s):  
K.V. Divya Lakshmi ◽  
T. Siva Rao
Keyword(s):  
Escherichia Coli ◽  
Anatase Phase ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
Orange Ii ◽  
Doped Tio2 ◽  
Optimum Reaction ◽  
Ft Ir ◽  
Co Doped

Nickel and sulfur co-doped TiO2 photocatalyst were prepared by using sol-gel method with dopants precursors of nickel nitrate and thiourea. Prepared samples were characterized by XRD, UV-Vis-DRS, TEM, BET, FT-IR and SEM-EDX. These characterization and experimental results revealed that there is a formation of anatase phase, decreased band gap 2.62 eV for NIST-2, small particle size 7.3 nm and high surface area 142.62 m2/g. The FT-IR frequency shift for Ti-O-Ti was observed from 569 cm-1 to 460-560 cm-1 for co-doped TiO2. The efficiency of photocatalytic and antibacterial was evaluated by degradation of Orange-II dye and Escherichia coli (MTCC-443) respectively. The complete degradation of Orange-II was achieved in 120 min at optimum reaction parameters for NIST-2 at pH-3, catalyst dosage-100 mg/L and initial dye concentration at 10 mg/L.

First-principle study of SO2 adsorption on Fe/Co-doped vacancy defected single-walled (8, 0) carbon nanotubes in sensor applications

2019 ◽  
Vol 18 (05) ◽  
pp. 1950025 ◽  
Author(s):  
Meng Zhang ◽  
Guoqing Li ◽  
Xiaomin Lu ◽  
Qianru Zhang ◽  
Wei Li
Keyword(s):  
Carbon Nanotubes ◽  
Density Functional ◽  
Energy Gap ◽  
Single Vacancy ◽  
Functional Theory ◽  
Sensor Applications ◽  
Co Doping ◽  
So2 Adsorption ◽  
Before And After ◽  
Co Doped

To explore the excellent sensor for detecting the pollution gas [Formula: see text], the adsorptions of [Formula: see text] molecule on the surfaces of Fe/Co-doped carbon nanotubes (CNTs) and single vacancy defected (8, 0) CNTs were investigated by using density functional theory (DFT). In addition, the adsorption energies, geometries, energy gaps and electronic structures were analyzed. The results showed that Fe/Co-doping and single-vacancy-defected can improve the adsorption and sensitiveness of CNTs toward [Formula: see text]. Considering the changes of energy gap before and after the [Formula: see text] molecule adsorbed on each modified CNTs and its adsorption strength, Fe-doped CNTs (Fe-CNTs) and Co-doped site-2 single-vacancy-defected CNTs performed better for detecting [Formula: see text] molecule. With the decreasing number of electrons of the doped atom (Fe, Co, Ni), the adsorption became more stable. The results of this paper are profound and meaningful for designing [Formula: see text] sensing devices.

Facile Synthesis and Effect of Eu, Tb Co-doping On the Tunable Luminescent Properties of YBO3

2013 ◽  
Vol 1497 ◽  
Author(s):  
Xianwen Zhang ◽  
Archis Marathe ◽  
Sandeep Sohal ◽  
Mark Holtz ◽  
Marauo Davis ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Three Dimensional ◽  
Visible Region ◽  
Luminescent Properties ◽  
Molar Ratio ◽  
Co Doping ◽  
Whole Process ◽  
High Resolution Tem ◽  
Alkaline Conditions ◽  
Co Doped

ABSTRACTEu3+/Tb3+co-doped YBO3 three-dimensional (3D) microstructures have been hydrothermally prepared by adjusting solvent and the molar ratio of Y3+ to B (Y/B) at 180 °C. The whole process was carried out under alkaline conditions without the use of any surfactant or catalyst. Characterizations of the samples are carried out using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). The photoluminescence (PL) colors of YBO3 sample co-doped with Eu3+ and Tb3+ under ultraviolet excitation can be tuned from red, through yellow and green-yellow, to green by changing the relative doping concentrations of the two activator ions. These phosphors with multicolor emissions in the visible region be potentially used as labels for light-display systems, optoelectronic devices and biological molecules.

scholarly journals PENGARUH PENAMBAHAN CO-DOPING Mg/La TERHADAP KARAKTERISASI TiO2 SEBAGAI FOTOELEKTRODA

2021 ◽  
Vol 9 (1) ◽  
pp. 79-86
Author(s):  
Mursal Mursal ◽  
◽  
Nurul Azmi ◽  
Ismail Ismail ◽  
◽  
...  
Keyword(s):  
Doping Concentration ◽  
Crystal Size ◽  
Energy Gap ◽  
Dopant Concentration ◽  
Sol Gel ◽  
Pure Tio2 ◽  
Tio2 Sample ◽  
Doped Tio2 ◽  
Co Doping ◽  
Co Doped

The effect of Mg/La co-doping addition on the caracteristics of TiO2 as photoelectrode have been studied. This study aims to investigate the effect of Mg/La co-doping concentration on the characteristics of TiO2. This study aims investigate the effect of Mg/La co-doping concentration on the characteristics of TiO2. Mg/La was varied from 0% mol, 0.4 / 0.6% mol, and 0.6 / 0.4% mol. Synthesis of TiO2 co-doping Mg/La was done by sol gel method. The resulting of powder pure TiO2 and co-doping Mg/La was made to paste, and was deposited on a glass substrate with a size of 2.5 x 2.5 cm and sintered at 600°C for 1 hour. Mg / La co-doped TiO2 layers were characterized using XRD, UV-Vis, and FTIR spectrometers. The results showed that TiO2 was the mos dominan phase appeared in pure TiO2 sample. The phase of MgO, MgTiO3, Mg2TiO4, and La2O3 were found in Mg/La co-doped TiO2 samples. The crystal size of Mg/La co-doped TiO2 was varied from 8.85 to 7.70 nm. In this research, we obtained that the energy gap was varied from 3.52 to 3.5 eV depent on co-dopant concentration. FTIR measurement showed groups of Ti-O, Ti-O-Ti, Ti-O-O, and H-O.

scholarly journals Sol-Gel Synthesized N and MN Co-Doped Tio2 Nanomaterial for Photocatalytic Degradation of Malathion under Visible Light Irradiation

2019 ◽  
Vol 9 (2) ◽  
pp. 3688-3694
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Visible Light Irradiation ◽  
Sol Gel ◽  
Light Irradiation ◽  
Average Particle ◽  
Doped Tio2 ◽  
Sem And Tem ◽  
Ft Ir ◽  
Co Doped

Different weight percentages (0.25-1.00 wt%) of Nitrogen (Non-Metal) and Manganese (Metal) co-doped nano titania were synthesized by sol-gel method and characterized by XRD, UV-vis.DRS, FT-IR, XPS, SEM and TEM. The XRD results has shown that all the prepared catalysts are in anatase phase indicating that co-doping of N and Mn did not affect the crystal structure of TiO2 . From the UV-vis.DRS spectra a significant absorption shift towards visible region was noticed in N and Mn co-doped TiO2 and their presence was confirmed by XPS and FT-IR results. SEM and TEM results showed spherical nanoparticles with average particle size of 9 nm. Photocatalytic efficiency of synthesized nano materials was tested on non-biodegradable organophosphorous pesticide, Malathion under visible light irradiation. The effect of dopant concentration, pH, catalyst dosage, and initial pesticide concentration on photocatalytic degradation of malathion was studied and optimum conditions were established. Among the synthesized samples 0.50 wt% N & 1.00 wt% Mn-TiO2 exhibited best photocatalytic performance. Photoluminiscent spectroscopy (PL) was used to examine the rate of production of oxidative species, hydroxyl radicals which play key role in photocatalytic degradation.

scholarly journals Facile microwave-assisted synthesis of Al:Mn co-doped PbI2 nanosheets: structural, vibrational, morphological, dielectric and radiation activity studies

2018 ◽  
Vol 36 (2) ◽  
pp. 320-326 ◽  
Author(s):  
I.S. Yahia ◽  
Mohd. Shkir ◽  
V. Ganesh ◽  
M.M. Abutalib ◽  
H.Y. Zahran ◽  
...  
Keyword(s):  
Single Crystal ◽  
Gamma Rays ◽  
Doping Concentration ◽  
Linear Attenuation Coefficient ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
Large Area ◽  
Co Doping ◽  
Ft Ir ◽  
Co Doped

Abstract Herein, we report a successful development of nano-scale pure and Al and Mn co-doped PbI2 using facile microwaveassisted route. Structural study was done through X-ray diffraction analysis of grain size, dislocation density and lattice strain. The crystallite size was found to vary from 28 nm to 40 nm due to Al:Mn co-doping in PbI2. The presence of various vibrational modes was confirmed by FT-IR spectroscopy and red shifting was observed in peak positions compared to the bulk. Surface morphology, examined using a scanning electron microscope, confirmed the formation of single crystal nanosheets of a thickness in the range of 10 nm to 30 nm. The single crystal nanosheets were found to be transformed to large area nanosheets due to the doping. Enhancement in dielectric constant from ~7.5 to 11 was observed with increasing Al doping concentration. Linear attenuation coefficient was calculated and showed the enhancement of blocking gamma rays with increasing doping concentration. Its value was found to increase from 7.5 to 12.8 with the doping. The results suggest that the synthesized nanostructures can be used for detection and absorption of gamma rays emitted by 137Cs and 241Am sources.

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