Doped sol–gel films vs. powders TiO 2 : On the positive effect induced by the presence of a substrate

Léonard, Géraldine; Malengreaux, Charline; Mélotte, Quentin; Lambert, Stéphanie D.; Bruneel, Els; Driessche, Isabel Van; Heinrichs, Benoı̂t

doi:10.1016/j.jece.2015.11.040

Cited by 22 publications

(14 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Films were also deposited on different sublayers to evaluate the versatility of deposition of the aqueous TiO 2 colloids. For bare and brush stainless steel substrates, two sublayers were tested: a sublayer of anatase TiO 2 synthesized as [29,41], calcined 1 h at 500 • C, and a sublayer of sol-gel SiO 2 synthesized according to [62]. For glass substrate, only anatase TiO 2 sublayer was evaluated.…”

Section: Film Depositionmentioning

confidence: 99%

“…Regarding the improvement of the recombination time, the major modification of TiO 2 materials is the addition of metallic nanoparticles or metallic ions as Ag [19,20], Au [19,21], Pt [22,23], Pd [20], Fe 3+ [24][25][26][27] or Cu 2+ [24,25,28]. In this case, the metallic nanoparticle or metallic ion plays a role of electron trap allowing to increase the recombination time [29]. Combination with other semiconductors has also been investigated [10] such as TiO 2 /ZnO [30], TiO 2 /CdS, TiO 2 /Bi 2 S 3 [10] or TiO 2 /ZrO 2 [31].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

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

et al. 2020

Self Cite

View full text Add to dashboard Cite

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.

show abstract

Section: Film Depositionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Moreover it can be carefully designed for many other applications [20]. A Sol-Gel process is commonly used to prepare TiO 2 in the form of a powder or film under mild synthesis conditions, and thus the anatase phase is selectively prepared, rather than the rutile phase [13,[21][22][23][24][25]. It is well-known that the anatase phase has a higher activity than the rutile phase [26].…”

Section: Introductionmentioning

confidence: 99%

Porphyrin-based hybrid silica-titania as a visible-light photocatalyst

Mahy

Páez

Carcel

et al. 2019

Journal of Photochemistry and Photobiology A: Chemistry

Self Cite

View full text Add to dashboard Cite

A silylated porphyrin derivative is co-hydrolyzed with Ti(OiPr)4 to produce a hybrid TiO2 photocatalyst, and three different ratios between porphyrin and TiO2 are made. In this way, the porphyrin fragments are held in the resulting matrix through strong Si-O-Ti covalent bonds to limit porphyrin leaching. Thanks to its photoactive character the porphyrin fragment can act as an actuator for the TiO2 to degrade organic pollutants using light from ultra-violet to the visible range. The photocatalysts are synthesized using an easy aqueous route allowing "green conditions" for synthesis. For comparative purposes, the corresponding pure TiO2 and a grafted catalyst are also synthesized and studied. For all samples, a mixture of anatase/brookite TiO2 is obtained, resulting in crystalline materials with low temperature synthesis. The three porphyrin-doped samples prepared in water prove to be efficient photocatalysts for the degradation of p-nitrophenol (PNP) under visible light, and an improvement in photoactivity is observed when the amount of porphyrin increases. The photocatalyst activity is very stable over time as the PNP degradation remains nearly constant after 264 h of testing, showing no leaching of porphyrin. In recycling tests, the grafted sample presents bond breaking between POR-Si and TiO2 and a decrease in photoactivity towards pure TiO2 sample activity. A comparison with the commercial Evonik P25 catalyst shows that the porphyrin-doped TiO2 is nearly 6 times more photoactive under visible light for PNP degradation.

show abstract

“…The crystallite size decreases (from 30 to 16 nm) when the SnO 2 amount increases (from 0 to 30 wt %), as observed on Figure 1, corresponding to the decreasing peak heights with the loading percentage. The introduction of SnO 2 in ZnCo 2 O 4 matrix probably disturbs the crystallization and slows the growth rates of the crystals as observed in previous studies when dopants were added [32].…”

Section: Morphology and Compositionmentioning

confidence: 68%

Visible Light Sensitive SnO2/ZnCo2O4 Material for the Photocatalytic Removal of Organic Pollutants in Water

et al. 2019

Self Cite

View full text Add to dashboard Cite

In this study, pure ZnCo2O4 and SnO2/ZnCo2O4 mix photocatalysts have been synthesized by the sol-gel process with three different SnO2 loading percentages (10, 20, and 30 wt %). Their photocatalytic activities were assessed on the degradation of organic pollutants in water under visible illumination. The structural, morphological, and optical properties were analyzed by X-ray diffraction (XRD), scanning electron microscopy, energy-dispersive X-ray (EDX), Fourier transform infrared (FTIR), nitrogen adsorption-desorption isotherms, X-ray photoelectron spectroscopy (XPS), and UV–Visible diffuse reflectance measurements. The results have shown that the materials are composed of a crystalline ZnCo2O4 matrix with a decrease in crystallite size with the amount of SnO2. Weakly crystalline SnO2 is also observed for loaded samples. The specific surface area is modified with the loading ratio. The evaluation of the photoactivity of the samples under visible light for the degradation of p-nitrophenol has highlighted that all materials are highly photoactive under visible light thanks to heterojunction between the two oxides. An application test has been conducted on a dye, congo red, showing the same tendencies. An optimal amount of SnO2 loading is observed for the sample containing 20 wt % of SnO2. A comparison with commercial Evonik P25 showed that the materials developed in this work have five to six times better efficiency under visible light, leading to a promising photocatalyst material.

show abstract

Doped sol–gel films vs. powders TiO 2 : On the positive effect induced by the presence of a substrate

Cited by 22 publications

References 48 publications

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

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

Porphyrin-based hybrid silica-titania as a visible-light photocatalyst

Visible Light Sensitive SnO2/ZnCo2O4 Material for the Photocatalytic Removal of Organic Pollutants in Water

Contact Info

Product

Resources

About