Catalytic photodegradation of dyes by in situ zeolite-supported titania

Petkowicz, Diego Ivan; Pergher, Sibele B. C.; Silva, Carlos Daniel Silva da; Rocha, Zildete; Santos, João Henrique Zimnoch dos

doi:10.1016/j.cej.2010.01.039

Cited by 49 publications

(16 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A strong absorption band around 350 nm was observed in all samples, which is associated with O 2 p → Ti 3 d transitions in the tetrahedral symmetry , . In the regions from 190–240 nm and 250–300 nm, two shoulders are observed, corresponding to electron transfer excitation from the ligand‐oxygen to an unoccupied orbital of the Ti 4+ framework . The typical absorption edge of the TiO 2 semiconductor was evidenced at 411 nm; however, the TF support and the CuO/TF photocatalysts absorbed at slightly higher wavelengths.…”

Section: Resultsmentioning

confidence: 89%

“…12,13 In the regions from 190-240 nm and 250-300 nm, two shoulders are observed, corresponding to electron transfer excitation from the ligand-oxygen to an unoccupied orbital of the Ti 4+ framework. 14 The typical absorption edge of the TiO 2 semiconductor was evidenced at 411 nm; however, the TF support and the CuO/TF photocatalysts absorbed at slightly higher wavelengths. Besides, the absorption edges of the CuO/TF materials extend toward wavelengths a little longer compared with the TF powder.…”

Section: Nitrogen Adsorptionmentioning

confidence: 97%

See 1 more Smart Citation

Improved photocatalytic hydrogen production from methanol/water solution using CuO supported on fluorinated TiO₂

Castañeda

Tzompantzi

Rodríguez-Rodríguez

et al. 2017

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

BACKGROUND Photocatalytic water splitting is an attractive alternative for hydrogen generation because it is considered a clean and environment‐friendly process. TiO2 semiconductor has been widely used in photocatalysis, however, its efficiency is limited due to the high recombination of the charge carriers. Many methods have been proposed to enhance TiO2 photoactivity, including modification with nonmetal ions and coupling with other semiconductor oxides. In this present work a series of CuO/TF photocatalysts with different CuO content were synthesized by impregnation of fluorinated TiO2 (TF) powder. These materials were characterized by several techniques and were studied in the hydrogen production reaction from a methanol/water solution under UV irradiation. RESULTS The impregnation of the TF powder with Cu(NO3)2•H2O leads to the generation of crystalline and mesoporous materials and the existence of copper in the form of CuO. HRTEM results indicated the formation of heterojunctions between TiO2 and CuO phases. CuO(1.0)/TF photocatalyst was four times more active than TiO2 and fluorinated TiO2 support. CONCLUSIONS The coexistence of fluoride and CuO species on TiO2 improves the photocatalytic properties of the semiconductor and the reduction of the H+ ions to H2 is considerably better than that achieved with TiO2, TF and CuO/TiO2 materials. © 2017 Society of Chemical Industry

show abstract

Section: Resultsmentioning

confidence: 89%

Section: Nitrogen Adsorptionmentioning

confidence: 97%

Improved photocatalytic hydrogen production from methanol/water solution using CuO supported on fluorinated TiO₂

Castañeda

Tzompantzi

Rodríguez-Rodríguez

et al. 2017

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

show abstract

“…While Zeolite NaA have the Si/Al ratio equal to 1, zeolite NaY have Si/Al ratio higher than 1.5. Thus, that indicates a higher proton acidity for zeolite NaA (Petkowicz, Pergher, Rochac, & Santos, 2010). Despite the low Si/Al ratio on zeolites NaA, they also have photocatalytic activity.…”

Section: Introductionmentioning

confidence: 96%

<b>Synergistic effect between oxides semiconductors and zeolites on photobleaching of RB250 textile dye

et al. 2018

View full text Add to dashboard Cite

The present work aims to evaluate the activity of semiconductor oxides (TiO 2 , Nb 2 O 5 and ZnO) supported on NaA and NaY zeolites, as well as their synergistic effect on Reactive Blue Dye (RB250) photodegradation process. Prior to deposition, TiO 2 particles size was reduced by ultrasonic scattering followed by filtration. The particles on the filtrate were used to conduct the experiments. The semiconductors were immobilized in concentrations of 2.5, 5 and 10% (w w -1 ) and the photocatalytic tests were performed at catalyst concentrations of 1 and 2 g L -1 . Moreover, supported catalysts were characterized by XRD, textural analysis, zero point of charge and temperature programmed desorption of NH 3 . A comparison between the supported catalysts showed high activity for the ones supported with ZnO and TiO 2 . Zeolite NaY has broader opened channels than NaA, which reduces the dye molecules blockage, and, as a result, increased the catalyst activity. A higher concentration of supported catalysts (2 g L -1 ) provides greater photocatalytic activity, while higher concentration of semiconductors immobilized on supports does not present significant differences.Efeito sinérgico entre óxidos semicondutores e zeólitas no fotoclareamento do corante têxtil RB250 RESUMO. O objetivo deste trabalho foi avaliar a atividade dos óxidos semicondutores (TiO 2 , Nb 2 O 5 & ZnO) suportados nas zeólitas NaA e NaY e seu efeito sinérgico na fotodegradação do corante têxtil azul reativo (RB250). Antes da deposição, o tamanho das partículas de TiO 2 foi reduzido por dispersão em ultrassom seguido por filtração e foram utilizadas as partículas que passaram através do filtro. Os semicondutores foram imobilizados em concentrações de 2,5, 5 e 10% (m m -1 ) e os testes fotocatalíticos foram realizados em concentrações de catalisador de 1 e 2 g L -1 . Os catalisadores suportados foram caracterizados por DRX, análise textural, ponto de carga zero e dessorção por temperatura programada. Os catalisadores suportados com ZnO e TiO 2 mostraram maior atividade do que o Nb 2 O 5 . Os testes fotocatalíticos indicaram um aumento na atividade dos catalisadores suportados em NaY sendo essa com resultados superiores aos encontrados com a zeólita NaA. Isso por causa dos seus canais mais estreitos que dificultam a entrada de moléculas do corante. A maior concentração de catalisadores suportados (2 g L -1 ) proporciona maior atividade fotocatalítica, enquanto a maior concentração de semicondutores imobilizados em suportes não apresenta diferenças significativas.

show abstract

“…Zeolites with their intrinsic properties possess cages and channels which assist in confining organic micropollutant molecules on their surface hence aiding enhanced photocatalytic activities. Zeolites ability to act as an electron donor or acceptor depends on their adsorption sites, an intrinsic ability that helps in the reduction of electron-hole pair recombination rates when TiO 2 is encapsulated on their surface [27,28].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of Rhodium Doped on TiO₂/HCP for Enhanced Photocatalytic Performance on Pentachlorophenol

Sanni

Idemudia

2014

Journal of Nanomaterials

View full text Add to dashboard Cite

Visible-light-responsive material based on Rhodium doped on titanium dispersed on dealuminated clinoptilolite (TiO2/HCP) was synthesized via a combination of the sol-gel method and photoreductive deposition technique. The photocatalyst surface characterization, structural and optical properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and UV-visible spectra (UV-VIS). Doping TiO2/HCP with Rh imparts a red shifting of the absorption band into the visible light region according to UV-VIS. The prepared composite materials were evaluated for their photocatalytic activities on pentachlorophenol (PCP) degradation under sunlight irradiation. The Rhodium doped TiO2/HCP exhibited enhanced photocatalytic activity and can be considered as a potential photocatalyst in wastewater treatment.

show abstract

Catalytic photodegradation of dyes by in situ zeolite-supported titania

Cited by 49 publications

References 37 publications

Improved photocatalytic hydrogen production from methanol/water solution using CuO supported on fluorinated TiO₂

Improved photocatalytic hydrogen production from methanol/water solution using CuO supported on fluorinated TiO₂

<b>Synergistic effect between oxides semiconductors and zeolites on photobleaching of RB250 textile dye

Synthesis and Characterization of Rhodium Doped on TiO₂/HCP for Enhanced Photocatalytic Performance on Pentachlorophenol

Contact Info

Product

Resources

About

Catalytic photodegradation of dyes by in situ zeolite-supported titania

Cited by 49 publications

References 37 publications

Improved photocatalytic hydrogen production from methanol/water solution using CuO supported on fluorinated TiO2

Improved photocatalytic hydrogen production from methanol/water solution using CuO supported on fluorinated TiO2

<b>Synergistic effect between oxides semiconductors and zeolites on photobleaching of RB250 textile dye

Synthesis and Characterization of Rhodium Doped on TiO2/HCP for Enhanced Photocatalytic Performance on Pentachlorophenol

Contact Info

Product

Resources

About

Improved photocatalytic hydrogen production from methanol/water solution using CuO supported on fluorinated TiO₂

Improved photocatalytic hydrogen production from methanol/water solution using CuO supported on fluorinated TiO₂

Synthesis and Characterization of Rhodium Doped on TiO₂/HCP for Enhanced Photocatalytic Performance on Pentachlorophenol