Efficient N, Fe Co-Doped TiO2 Active under Cost-Effective Visible LED Light: From Powders to Films

An eco-friendly photocatalytic coating, active under a cost-effective near-visible LED system, was synthesized without any calcination step for the removal of organic pollutants. Three types of doping (Fe, N and Fe + N), with different dopant/Ti molar ratios, were investigated and compared with undoped TiO2 and the commercial P25 photocatalyst. Nano-crystalline anatase-brookite particles were successfully produced with the aqueous sol-gel process, also at a larger scale. All samples displayed a higher visible absorption and specific surface area than P25. Photoactivity of the catalyst powders was evaluated through the degradation of p-nitrophenol in water under visible light (>400 nm). As intended, all samples were more performant than P25. The N-doping, the Fe-doping and their combination promoted the activity under visible light. Films, coated on three different substrates, were then compared. Finally, the photoactivity of a film, produced from the optimal N-Fe co-doped colloid, was evaluated on the degradation of (i) p-nitrophenol under UV-A light (365 nm) and (ii) rhodamine B under LED visible light (395 nm), and compared to undoped TiO2 film. The higher enhancement is obtained under the longer wavelength (395 nm). The possibility of producing photocatalytic films without any calcination step and active under low-energy LED light constitutes a step forward for an industrial development.

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

Catalysts ◽

10.3390/catal11020235 ◽

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.

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Preparation and Characterization of Visible-Light-Activated Fe-N Co-Doped TiO2and Its Photocatalytic Inactivation Effect on Leukemia Tumors

International Journal of Photoenergy ◽

10.1155/2012/631435 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 8

Author(s):

Kangqiang Huang ◽

Li Chen ◽

Jianwen Xiong ◽

Meixiang Liao

Keyword(s):

Electron Microscope ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Light Therapy ◽

Cell Counting ◽

Visible Absorption ◽

X Ray ◽

Photocatalytic Inactivation ◽

Inactivation Efficiency ◽

Co Doped

The Fe-N co-doped TiO2nanocomposites were synthesized by a sol-gel method and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), ultraviolet-visible absorption spectroscopy (UV-vis) and X-ray photoelectron spectroscopy (XPS). Then the photocatalytic inactivation of Fe-N-doped TiO2on leukemia tumors was investigated by using Cell Counting Kit-8 (CCK-8) assay. Additionally, the ultrastructural morphology and apoptotic percentage of treated cells were also studied. The experimental results showed that the growth of leukemic HL60 cells was significantly inhibited in groups treated with TiO2nanoparticles and the photocatalytic activity of Fe-N-TiO2was significantly higher than that of Fe-TiO2and N-TiO2, indicating that the photocatalytic efficiency could be effectively enhanced by the modification of Fe-N. Furthermore, when 2 wt% Fe-N-TiO2nanocomposites at a final concentration of 200 μg/mL were used, the inactivation efficiency of 78.5% was achieved after 30-minute light therapy.

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Preparation of Novel Ag–Si–TiO2 Composite and Research on Its Photocatalytic Degradation of Formaldehyde

Science of Advanced Materials ◽

10.1166/sam.2021.3864 ◽

2021 ◽

Vol 13 (3) ◽

pp. 371-380

Author(s):

Yongjun Wu ◽

Nina Xie ◽

Lu Yu

Keyword(s):

Photoelectron Spectroscopy ◽

Removal Rate ◽

Sol Gel ◽

Catalytic Performance ◽

Formaldehyde Concentration ◽

Order Kinetic ◽

Solution Ph ◽

Visible Absorption ◽

X Ray ◽

Co Doped

A novel Ag–Si–TiO2 composite was prepared via sol–gel method for removing residual formaldehyde in shiitake mushroom. The structure of Ag–Si–TiO2 composite was characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses. Ultraviolet-visible absorption spectroscopy (UV-Vis) and N2 adsorption-desorption tests showed that Ag and Si co-doped decreased the band gap, the Brunauer-Emmett-Teller (BET) specific surface area of the samples increased and the recombination probability of electron-hole pairs (e--h+) reduced. Effect on removal rate of formaldehyde with different Ag-Si co-doped content, formaldehyde concentration and solution pH were investigated, and the results showed that 6.0 wt%Ag-3.0 wt%Si-TiO2 samples had an optimum catalytic performance, and the degradation efficiency reached 96.6% after 40 W 365 nm UV lamp irradiation for 360 min. The kinetics of formaldehyde degradation by Ag–Si–TiO2 composite photocatalyst could be described by Langmuir-Hinshelwood first-order kinetic model.

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Preparation of C, N and P co-doped TiO2 and its photocatalytic activity under visible light

Functional Materials Letters ◽

10.1142/s1793604719500450 ◽

2019 ◽

Vol 12 (04) ◽

pp. 1950045 ◽

Cited By ~ 3

Author(s):

Lin Zhao ◽

Yanzhao Xie ◽

Qiuyu Lin ◽

Rongze Zheng ◽

Yong Diao

Keyword(s):

Visible Light ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

Soluble Starch ◽

Doping Amount ◽

X Ray ◽

Composite Catalysts ◽

One Step ◽

Co Doped

A series of composite catalysts of C, N and P co-doped TiO2 were prepared by sol-gel method, using a biomass (soluble starch) dopant. The samples were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (DRS), fourier transform infrared (FTIR) spectroscopy. The results show that TiO2 is co-doped with C, N and P by one step. The resulting composite exhibited higher specific surface area, wider visible-light absorption band with respect to the pure TiO2. The sample calcined at 400∘C for 2[Formula: see text]h with a doping amount of 6[Formula: see text]g soluble starch showed the best electrochemical performance. The C, N and P co-doped TiO2 was also used for the degradation of methylene blue (MB) and degradation ratio was up to 98% in 80[Formula: see text]min under visible light irradiation.

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The fabrication of visible light responsive Ag-SiO 2 co-doped TiO 2 thin films by the sol–gel method

Advances in Natural Sciences Nanoscience and Nanotechnology ◽

10.1088/2043-6254/1/1/015007 ◽

2010 ◽

Vol 1 (1) ◽

pp. 015007 ◽

Cited By ~ 7

Author(s):

Duy Dam Le ◽

Thi My Dung Dang ◽

Vinh Thang Chau ◽

Mau Chien Dang

Keyword(s):

Thin Films ◽

Visible Light ◽

Sol Gel ◽

Gel Method ◽

Sol Gel Method ◽

Co Doped

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Photocatalytic Improvement under Visible Light inTiO2Nanoparticles by Carbon Nanotube Incorporation

Journal of Nanomaterials ◽

10.1155/2015/689306 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 13

Author(s):

Mathana Wongaree ◽

Siriluk Chiarakorn ◽

Surawut Chuangchote

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Sol Gel ◽

Multiwall Carbon Nanotubes ◽

High Specific Surface Area ◽

Molar Ratio ◽

Molar Ratios ◽

Calcination Temperatures ◽

Photocatalytic Activities ◽

Multiwall Carbon

Photocatalytic activity ofTiO2nanoparticles was successfully enhanced by addition of multiwall carbon nanotubes (MWCNT) to make CNT/TiO2nanocomposites by sol-gel method at ambient temperature. CNT treated by HNO3 : H2SO4treatment (1 : 3 v/v) was mixed withTiO2nanoparticles at various molar ratios and calcination temperatures. The optimal molar ratio of CNT : TiO2was found at 0.05 : 1 by weight. The optimal calcination condition was 400°C for 3 h. From the results, the photocatalytic activities of CNT/TiO2nanocomposites were determined by the decolorization of 1 × 10−5 M methylene blue (MB) under visible light. CNT/TiO2nanocomposites could enhance the photocatalytic activity and showed faster for the degradation of MB with only 90 min. The degradation efficiency of the MB solution with CNT/TiO2nanocomposite achieved 70% which was higher than that with pristineTiO2(22%). This could be explained that CNT preventsTiO2from its agglomeration which could further enhance electron transfer in the composites. In addition, CNT/TiO2nanocomposites had high specific surface area (202 m2/g) which is very promising for utilization as a photocatalyst for environmental applications.

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Preparation, Characterization, and Photocatalytic Property of N-La Co-Doped TiO2 with Visible Light Response

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.529.537 ◽

2012 ◽

Vol 529 ◽

pp. 537-540 ◽

Cited By ~ 1

Author(s):

Gui Hua Li ◽

An Feng Wang

Keyword(s):

Visible Light ◽

Reaction Temperature ◽

Catalyst Activity ◽

Sol Gel ◽

Photocatalytic Property ◽

Light Response ◽

Catalyst Amount ◽

Doped Tio2 ◽

Sol Gel Process ◽

Co Doped

N-La co-doped TiO2 has been synthesized via sol-gel process. The XRD result showed that the structure of N-La co-doped TiO2 was anatase. Their performance of photocatalytic degradation of methylene blue under visible light were investigated. The combined effects of catalyst compsition, calcination temperature, catalyst amount and reaction temperature on catalyst activity were investigated. Experiment results depicted that activeness of catalyst N2.5La0.5/TiO2 calcinated at 500°C for 2h was highest. Using this catalyst, when the catalyst amount was 0.35 g/L, the reaction temperature was 40°C the degradation rate of mehylene blue in 4h could reach 96.5%.

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Effective visible light-active boron and europium co-doped BiVO4 synthesized by sol–gel method for photodegradion of methyl orange

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2013.08.063 ◽

2013 ◽

Vol 262 ◽

pp. 447-455 ◽

Cited By ~ 82

Author(s):

Min Wang ◽

Yinsheng Che ◽

Chao Niu ◽

Mingyan Dang ◽

Duo Dong

Keyword(s):

Methyl Orange ◽

Visible Light ◽

Sol Gel ◽

Gel Method ◽

Sol Gel Method ◽

Visible Light Active ◽

Co Doped

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Effective Dye Degradation Using Sol-Gel Synthesized Titania Nanostructures

Current Analytical Chemistry ◽

10.2174/1573411016999200409122724 ◽

2020 ◽

Vol 16 ◽

Author(s):

Priyanka Karathan Parakkandy ◽

Kagalagodu Manjunthiah Balakrishna ◽

Thomas Varghese

Keyword(s):

Methylene Blue ◽

Visible Light ◽

Crystallite Size ◽

Organic Dyes ◽

Dye Degradation ◽

Sol Gel ◽

Blue Shift ◽

Degradation Process ◽

Rutile Phase ◽

Visible Absorption

Background: The organic effluents from industry remain one of the reasons for water contamination. By natural degradation process, it is difficult to remove this; hence finding an effective solution for this is inevitable. TiO2-based materials have received enormous attention in the area of semiconductor photocatalysis, particularly for the degradation of organic dyes. This work emphasize on the degradation of two industrial dyes methylene blue and rhodamine blue by visible light irradiation of TiO2 based nanoparticles. Methods: In the present study, pristine and La3+ and Ce3+ doped nanotitania were synthesized by sol-gel method. The samples under investigation were characterized using X-ray diffraction, Transmission electron microscopy to study the variation of crystallite size and UV-Visible absorption spectroscopy. Results: The increase in crystallite size for the pristine samples calcined at various temperatures confirms the effect of calcination temperature. Also, the doping reduced the size of the synthesized nanotitania. Visible light extended absorption spectra have been observed for the calcined samples and Ce3+ doped nanotitania. The La3+ doped sample showed a blue shift in the absorption confirming quantum confinement. The photocatalytic activity in the context of degradation of certain industrial dyes such as methylene blue and rhodamine blue has been investigated for the samples. Conclusion: The studies found that nanotitania consisting of mixed anatase-rutile phase exhibits higher degradation efficiency than that of pure anatase or rutile samples. Besides, photocatalytic dye degradation has been significantly improved for Ce3+ doped nanotitania compared to the pristine sample.

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