N-Doped titanium dioxide nanosheets: Preparation, characterization and UV/visible-light activity

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F18%3A00490488" target="_blank" >RIV/61388955:_____/18:00490488 - isvavai.cz</a>

Alternative codes found

RIV/61388980:_____/18:00490488 RIV/60461373:22310/18:43917375

Result on the web

<a href="http://dx.doi.org/10.1016/j.apcatb.2018.03.053" target="_blank" >http://dx.doi.org/10.1016/j.apcatb.2018.03.053</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.apcatb.2018.03.053" target="_blank" >10.1016/j.apcatb.2018.03.053</a>

Result language

angličtina

Original language name

N-Doped titanium dioxide nanosheets: Preparation, characterization and UV/visible-light activity

Original language description

A series of nitrogen-doped 2D-titanium dioxide nanosheets was synthesized via green and facile procedure from the lyophilized aqueous colloids of peroxo titanic acid by urea addition and annealing in the temperature range of 350-500 degrees C. Detailed structural characterization (SEM, TEM with EDX, XRD) of N-doped TiO2 confirmed their 2D-foil morphology composed of packed anatase nanocrystals. CHNS analysis showed that the total nitrogen content in the N-doped TiO2 nanosheets is comparable (0.3 wt. %), and as shown in the EPR measurements in solid state, the annealing temperature determines the character of the nitrogen species incorporated in the anatase lattice. Paramagnetic nitrogen bulk centers (N-b(.)) dominate the X- and Q-band EPR spectra of the synthesized N-doped TiO2 annealed up to 400 degrees C, while NO species were detected in samples annealed at higher temperatures. The photoexcitation of the N-doped anatase nanosheets resulted in an intense increase of the N-b(.) signal intensity, especially upon VIS-light exposure, reflecting the selective photoexcitation of the material via diamagnetic N-b(-), centers. Nevertheless, the situation upon irradiation of dispersed systems is rather different and to link the information on the structure of the nanosheets with their photoinduced performance in suspensions, the indirect techniques of EPR spectroscopy were applied. Effective generation of paramagnetic reactive oxygen species (ROS) upon UV photoexcitation of the N-doped TiO2 nanopowders dispersed in water or dimethylsulfoxide was confirmed by EPR spin trapping technique. The VIS-light-induced ROS formation was significantly lower and correlates well with the results obtained by the photocatalytic decomposition of 4-chlorophenol upon VIS light. Even though the center dot OH-induced capacity of N-doped TiO2 prevails upon UV exposure, the VIS irradiation evokes the formation of photoelectrons capable of the selective reduction processes as demonstrated by the one-electron reduction of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) radical cation, where the form of nitrogen dopant (e. g. the presence of N-b(-)/N-b(.)) in the anatase structure showed a clear effect on the reaction rate. The prepared visible-light active N-doped TiO2 nanosheets exhibiting also adequate UV photoactivity represent promising materials for further development of solar-light active photocatalysts.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

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

Publication year

2018

Confidentiality

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

Name of the periodical

Applied Catalysis B - Environmental

ISSN

0926-3373

e-ISSN

—

Volume of the periodical

232

Issue of the periodical within the volume

SEP

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

12

Pages from-to

397-408

UT code for WoS article

000434004300044

EID of the result in the Scopus database

2-s2.0-85044611201