Preparation of nanocrystalline TiO2 monoliths by using modified supercritical carbon dioxide

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F18%3A10380459" target="_blank" >RIV/00216208:11320/18:10380459 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985858:_____/18:00490283 RIV/61989100:27710/18:10239703

Výsledek na webu

<a href="https://doi.org/10.1016/j.supflu.2018.02.001" target="_blank" >https://doi.org/10.1016/j.supflu.2018.02.001</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.supflu.2018.02.001" target="_blank" >10.1016/j.supflu.2018.02.001</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Preparation of nanocrystalline TiO2 monoliths by using modified supercritical carbon dioxide

Popis výsledku v původním jazyce

A flow supercritical fluid crystallization with and without modifier/s was applied to prepare nanocrystalline TiO2 monoliths without subsequent thermal treatment. The effect of processing conditions (temperature, pressure, water concentration, type of modifier: water or ethanol and water) on the crystallization, texture and purity of TiO2 was investigated. Gel blocks for processing were prepared by nitric acid-catalysed sol-gel synthesis. It was revealed that one- or multi-step processing by scCO(2) with modifier leads to direct crystallization of TiO2 monoliths of anatase-brookite crystal structure even at mild processing temperature of 40 degrees C and 30 MPa. 15 wt. % of water was determined to be the optimal concentration of water in scCO(2) as a crystallization agent. Processing temperature affected the anatase and brookite crystallite-size. Processing pressure affected the crystallization and purity of monolithic TiO2. The pre-drying as well as the post-drying by scCO(2) at 40 degrees C visibly improved the solidity of TiO2 monolith and stabilized brookite crystallites.

Název v anglickém jazyce

Preparation of nanocrystalline TiO2 monoliths by using modified supercritical carbon dioxide

Popis výsledku anglicky

A flow supercritical fluid crystallization with and without modifier/s was applied to prepare nanocrystalline TiO2 monoliths without subsequent thermal treatment. The effect of processing conditions (temperature, pressure, water concentration, type of modifier: water or ethanol and water) on the crystallization, texture and purity of TiO2 was investigated. Gel blocks for processing were prepared by nitric acid-catalysed sol-gel synthesis. It was revealed that one- or multi-step processing by scCO(2) with modifier leads to direct crystallization of TiO2 monoliths of anatase-brookite crystal structure even at mild processing temperature of 40 degrees C and 30 MPa. 15 wt. % of water was determined to be the optimal concentration of water in scCO(2) as a crystallization agent. Processing temperature affected the anatase and brookite crystallite-size. Processing pressure affected the crystallization and purity of monolithic TiO2. The pre-drying as well as the post-drying by scCO(2) at 40 degrees C visibly improved the solidity of TiO2 monolith and stabilized brookite crystallites.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

<a href="/cs/project/GA14-23274S" target="_blank" >GA14-23274S: Nekonvenční příprava nanostrukturovaných oxidů kovů pomocí přetlakových a superkritických tekutin</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Supercritical Fluids

ISSN

0896-8446

e-ISSN

—

Svazek periodika

137

Číslo periodika v rámci svazku

červenec

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

8

Strana od-do

93-100

Kód UT WoS článku

000431163500012

EID výsledku v databázi Scopus

2-s2.0-85044478433