Comparative study of nanocrystalline titanium dioxide obtained through sol–gel and sol–gel–hydrothermal synthesis

Seck, E.I.; Doña-Rodrı́guez, J.M.; Melián, E. Pulido; Fernández-Rodríguez, C.; Díaz, O. González; Portillo-Carrizo, D.; Pérez‐Peña, J.

doi:10.1016/j.jcis.2013.03.019

Cited by 26 publications

(12 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It can be appreciated that, in all cases, a single peak corresponding to Ti‐O‐Ti bonds appears around 690 cm −1 . However, while commercial catalyst and catalysts synthesized from isopropyl alcohol (a and c) do not show other peaks worth mentioning, catalysts obtained from ethanol (b and d) possess a band around 1640 cm −1 that can be linked to chemisorbed water, as well as a wide band between 3690 and 3000 cm −1 related to hydroxyl groups of adsorbed water molecules . The presence of these peaks has also been observed in catalysts synthesized through the traditional hydrothermal method and are usually considered favourable for photocatalytic processes …”

Section: Resultsmentioning

confidence: 73%

“…36 However, while commercial catalyst and catalysts synthesized from isopropyl alcohol (a and c) do not show other peaks worth mentioning, catalysts obtained from ethanol (b and d) possess a band around 1640 cm −1 that can be linked to chemisorbed water, as well as a wide band between 3690 and 3000 cm −1 related to hydroxyl groups of adsorbed water molecules. 37 The presence of these peaks has also been observed in catalysts synthesized through the traditional hydrothermal method and are usually considered favourable for photocatalytic processes. 38 In this sense, as in the case of the specific surface area, the combinations with ethanol would lead to an appropriate surface composition for the photocatalytic process.…”

Section: Adsorption Of Reactantsmentioning

confidence: 96%

See 1 more Smart Citation

Preparation of TiO₂-based catalysts with supercritical fluid technology: characterization and photocatalytic activity in CO₂reduction

Camarillo

Tostón

Martínez

et al. 2017

J. Chem. Technol. Biotechnol

View full text Add to dashboard Cite

BACKGROUND Titanium dioxide is the photocatalyst par excellence in environmental applications. Nevertheless, over the years various methods aiming to improve its efficiency have been presented. Herein, we report that TiO2 synthesis in supercritical medium can result in a significant enhancement in the rate of CO2 photocatalytic conversion. RESULTS Specifically, catalysts obtained from two titanium precursors (titanium tetraisopropoxide and diisopropoxititanium bis(acetylacetonate)) and two alcohols (ethanol and isopropyl alcohol) by hydrothermal synthesis in supercritical CO2 are shown to exhibit improved properties in comparison with the standard reference catalyst (Degussa P‐25, Evonik). CONCLUSION In particular, upgraded characteristics are related to reactants adsorption (higher specific surface areas, presence of surface hydroxyl groups), light absorption and excitation (better absorbance in visible range, lower band gap energy), and charge separation (appropriate morphology and crystallinity). Furthermore, when these catalysts are tested in the photocatalytic reduction of CO2, CO and CH4 production rates 3‐ and 15.7‐fold higher than those corresponding to the commercial catalyst have been found. © 2016 Society of Chemical Industry

show abstract

Section: Resultsmentioning

confidence: 73%

Section: Adsorption Of Reactantsmentioning

confidence: 96%

Preparation of TiO₂-based catalysts with supercritical fluid technology: characterization and photocatalytic activity in CO₂reduction

Camarillo

Tostón

Martínez

et al. 2017

J. Chem. Technol. Biotechnol

View full text Add to dashboard Cite

show abstract

“…In the field of catalysis, numerous works have shown that the synthesis conditions of a catalyst have strong influence on its properties [98][99][100], so the reactivity of synthetic solids could exceed that of commercial catalysts provided that an appropriate synthesis method is employed. A clear example of this is found in wastewater reclamation [101].…”

Section: Overview On Supercritical Fluids and Their Use To Produce Phmentioning

confidence: 99%

Greenhouse Effect Mitigation Through Photocatalytic Technology

Rincón

Camarillo

Martínez

et al. 2014

Environment, Energy and Climate Change I

View full text Add to dashboard Cite

Climate change is one of the most critical issues facing the world. One of the pillars of the fight against this phenomenon is the mitigation of greenhouse gas (GHG) emissions, CO 2 in particular. Although many achievements have already been made in CO 2 capture and storage technologies, promising methods to convert waste streams concentrated in this gas into valuable products are currently under way. This chapter intends to describe one of them, the photocatalytic reduction of CO 2 to fuel products, that is, the reaction to produce fuel between the CO 2 molecules and a reducing agent (usually water), in the presence of a semiconductor material that provides electrons (e À ) and holes (h + ) when it is illuminated by light of appropriate energy. Moreover, if solar energy were employed as light source, this type of energy difficult to store could be transformed into liquid or gaseous fuels, useful in conventional power production systems. In this chapter, firstly, a wide review about photocatalysis fundamentals, photocatalysts, synthesis of particles in supercritical fluids, characterization techniques, photocatalytic reactors, etc., is carried out. Subsequently, previous results from the authors' research on this subject are shown. More specifically, the characteristics of photocatalysts synthesized in a supercritical medium to convert CO 2 into fuels are presented and discussed.

show abstract

“…Synthetic powders are products of reaction carried out between precursors of different metals. However, hydrated mixed oxides can be obtained in hydro-or solvothermal conditions [13][14][15].…”

Section: Introductionmentioning

confidence: 99%

The sol–gel approach as a method of synthesis of xMgO·ySiO2 powder with defined physicochemical properties including crystalline structure

Ciesielczyk

Przybysz

Zdarta

et al. 2014

J Sol-Gel Sci Technol

View full text Add to dashboard Cite

The physicochemical properties of synthetic powders depend strongly on the method of their preparation. The present work concerns the use of the sol-gel method to prepare xMgOÁySiO 2 powders with defined physicochemical and structural properties. An important objective was to determine how the basic process parameters (including the type and concentration of the reactants) influence the physicochemical properties of the resulting material. To obtain a synthetic powders, organic precursors of magnesium (magnesium ethoxide), and silicon (tetraethoxysilane) were used. Selected products were subjected to calcination to identify the crystalline structure of the powders and to determine the impact of the proposed method of preparation on this parameter. This aspect of the research will significantly improve the range of application of the manufactured products. The powders obtained by the proposed method were thoroughly analyzed in terms of chemical composition, crystalline structure, morphology and nature of dispersion, parameters of porous structure, and thermal as well as electrokinetic properties. The solgel process proved very effective in the synthesis of highly active powders, as evidenced by the very high values obtained for the products' surface area. It was also confirmed that the physicochemical parameters are strongly dependent on the mass ratio of the reactants and on the method of final treatment of the precipitates.

show abstract

Comparative study of nanocrystalline titanium dioxide obtained through sol–gel and sol–gel–hydrothermal synthesis

Cited by 26 publications

References 63 publications

Preparation of TiO₂-based catalysts with supercritical fluid technology: characterization and photocatalytic activity in CO₂reduction

Preparation of TiO₂-based catalysts with supercritical fluid technology: characterization and photocatalytic activity in CO₂reduction

Greenhouse Effect Mitigation Through Photocatalytic Technology

The sol–gel approach as a method of synthesis of xMgO·ySiO2 powder with defined physicochemical properties including crystalline structure

Contact Info

Product

Resources

About

Comparative study of nanocrystalline titanium dioxide obtained through sol–gel and sol–gel–hydrothermal synthesis

Cited by 26 publications

References 63 publications

Preparation of TiO2-based catalysts with supercritical fluid technology: characterization and photocatalytic activity in CO2reduction

Preparation of TiO2-based catalysts with supercritical fluid technology: characterization and photocatalytic activity in CO2reduction

Greenhouse Effect Mitigation Through Photocatalytic Technology

The sol–gel approach as a method of synthesis of xMgO·ySiO2 powder with defined physicochemical properties including crystalline structure

Contact Info

Product

Resources

About

Preparation of TiO₂-based catalysts with supercritical fluid technology: characterization and photocatalytic activity in CO₂reduction

Preparation of TiO₂-based catalysts with supercritical fluid technology: characterization and photocatalytic activity in CO₂reduction