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Nonstoichiometric oxygen in Mn-Ga-O spinels : Reduction features of the oxides and their catalytic activity. / Bulavchenko, O. A.; Venediktova, O. S.; Afonasenko, T. N. et al.

In: RSC Advances, Vol. 8, No. 21, 01.01.2018, p. 11598-11607.

Research output: Contribution to journal › Article › peer-review

Harvard

Bulavchenko, OA, Venediktova, OS, Afonasenko, TN, Tsyrul'Nikov, PG, Saraev, AA, Kaichev, VV & Tsybulya, SV 2018, 'Nonstoichiometric oxygen in Mn-Ga-O spinels: Reduction features of the oxides and their catalytic activity', RSC Advances, vol. 8, no. 21, pp. 11598-11607. https://doi.org/10.1039/c7ra11557a

APA

Bulavchenko, O. A., Venediktova, O. S., Afonasenko, T. N., Tsyrul'Nikov, P. G., Saraev, A. A., Kaichev, V. V., & Tsybulya, S. V. (2018). Nonstoichiometric oxygen in Mn-Ga-O spinels: Reduction features of the oxides and their catalytic activity. RSC Advances, 8(21), 11598-11607. https://doi.org/10.1039/c7ra11557a

Vancouver

Bulavchenko OA, Venediktova OS, Afonasenko TN, Tsyrul'Nikov PG, Saraev AA, Kaichev VV et al. Nonstoichiometric oxygen in Mn-Ga-O spinels: Reduction features of the oxides and their catalytic activity. RSC Advances. 2018 Jan 1;8(21):11598-11607. doi: 10.1039/c7ra11557a

Author

Bulavchenko, O. A. ; Venediktova, O. S. ; Afonasenko, T. N. et al. / Nonstoichiometric oxygen in Mn-Ga-O spinels : Reduction features of the oxides and their catalytic activity. In: RSC Advances. 2018 ; Vol. 8, No. 21. pp. 11598-11607.

BibTeX

@article{ff6df0eb20eb4c19955f1295aac62e31,
title = "Nonstoichiometric oxygen in Mn-Ga-O spinels: Reduction features of the oxides and their catalytic activity",
abstract = "The subject of this study was the content of oxygen in mixed oxides with the spinel structure Mn1.7Ga1.3O4 that were synthesized by coprecipitation and thermal treatment in argon at 600-1200 °C. The study revealed the presence of excess oxygen in {"}low-temperature{"} oxides synthesized at 600-800 °C. The occurrence of superstoichiometric oxygen in the structure of Mn1.7Ga1.3O4+δ oxide indicates the formation of cationic vacancies, which shows up as a decreased lattice parameter in comparison with {"}high-temperature{"} oxides synthesized at 1000-1200 °C; the additional negative charge is compensated by an increased content of Mn3+ cations according to XPS. The low-temperature oxides containing excess oxygen show a higher catalytic activity in CO oxidation as compared to the high-temperature oxides, the reaction temperature was 275 °C. For oxides prepared at 600 and 800 °C, catalytic activity was 0.0278 and 0.0048 cm3 (CO) per g per s, and further increase in synthesis temperature leads to a drop in activity to zero. The process of oxygen loss by Mn1.7Ga1.3O4+δ was studied in detail by TPR, in situ XRD and XPS. It was found that the hydrogen reduction of Mn1.7Ga1.3O4+δ proceeds in two steps. In the first step, excess oxygen is removed, Mn1.7Ga1.3O4+δ → Mn1.7Ga1.3O4. In the second step, Mn3+ cations are reduced to Mn2+ in the spinel structure with a release of manganese oxide as a single crystal phase, Mn1.7Ga1.3O4 → Mn2Ga1O4 + MnO.",
keywords = "THIN-FILMS, OXIDATION, CO, NANOPARTICLES, PERFORMANCE, MN2O3",
author = "Bulavchenko, {O. A.} and Venediktova, {O. S.} and Afonasenko, {T. N.} and Tsyrul'Nikov, {P. G.} and Saraev, {A. A.} and Kaichev, {V. V.} and Tsybulya, {S. V.}",
note = "This journal is {\textcopyright} The Royal Society of Chemistry.",
year = "2018",
month = jan,
day = "1",
doi = "10.1039/c7ra11557a",
language = "English",
volume = "8",
pages = "11598--11607",
journal = "RSC Advances",
issn = "2046-2069",
publisher = "ROYAL SOC CHEMISTRY",
number = "21",

}

RIS

TY - JOUR

T1 - Nonstoichiometric oxygen in Mn-Ga-O spinels

T2 - Reduction features of the oxides and their catalytic activity

AU - Bulavchenko, O. A.

AU - Venediktova, O. S.

AU - Afonasenko, T. N.

AU - Tsyrul'Nikov, P. G.

AU - Saraev, A. A.

AU - Kaichev, V. V.

AU - Tsybulya, S. V.

N1 - This journal is © The Royal Society of Chemistry.

PY - 2018/1/1

Y1 - 2018/1/1

N2 - The subject of this study was the content of oxygen in mixed oxides with the spinel structure Mn1.7Ga1.3O4 that were synthesized by coprecipitation and thermal treatment in argon at 600-1200 °C. The study revealed the presence of excess oxygen in "low-temperature" oxides synthesized at 600-800 °C. The occurrence of superstoichiometric oxygen in the structure of Mn1.7Ga1.3O4+δ oxide indicates the formation of cationic vacancies, which shows up as a decreased lattice parameter in comparison with "high-temperature" oxides synthesized at 1000-1200 °C; the additional negative charge is compensated by an increased content of Mn3+ cations according to XPS. The low-temperature oxides containing excess oxygen show a higher catalytic activity in CO oxidation as compared to the high-temperature oxides, the reaction temperature was 275 °C. For oxides prepared at 600 and 800 °C, catalytic activity was 0.0278 and 0.0048 cm3 (CO) per g per s, and further increase in synthesis temperature leads to a drop in activity to zero. The process of oxygen loss by Mn1.7Ga1.3O4+δ was studied in detail by TPR, in situ XRD and XPS. It was found that the hydrogen reduction of Mn1.7Ga1.3O4+δ proceeds in two steps. In the first step, excess oxygen is removed, Mn1.7Ga1.3O4+δ → Mn1.7Ga1.3O4. In the second step, Mn3+ cations are reduced to Mn2+ in the spinel structure with a release of manganese oxide as a single crystal phase, Mn1.7Ga1.3O4 → Mn2Ga1O4 + MnO.

AB - The subject of this study was the content of oxygen in mixed oxides with the spinel structure Mn1.7Ga1.3O4 that were synthesized by coprecipitation and thermal treatment in argon at 600-1200 °C. The study revealed the presence of excess oxygen in "low-temperature" oxides synthesized at 600-800 °C. The occurrence of superstoichiometric oxygen in the structure of Mn1.7Ga1.3O4+δ oxide indicates the formation of cationic vacancies, which shows up as a decreased lattice parameter in comparison with "high-temperature" oxides synthesized at 1000-1200 °C; the additional negative charge is compensated by an increased content of Mn3+ cations according to XPS. The low-temperature oxides containing excess oxygen show a higher catalytic activity in CO oxidation as compared to the high-temperature oxides, the reaction temperature was 275 °C. For oxides prepared at 600 and 800 °C, catalytic activity was 0.0278 and 0.0048 cm3 (CO) per g per s, and further increase in synthesis temperature leads to a drop in activity to zero. The process of oxygen loss by Mn1.7Ga1.3O4+δ was studied in detail by TPR, in situ XRD and XPS. It was found that the hydrogen reduction of Mn1.7Ga1.3O4+δ proceeds in two steps. In the first step, excess oxygen is removed, Mn1.7Ga1.3O4+δ → Mn1.7Ga1.3O4. In the second step, Mn3+ cations are reduced to Mn2+ in the spinel structure with a release of manganese oxide as a single crystal phase, Mn1.7Ga1.3O4 → Mn2Ga1O4 + MnO.

KW - THIN-FILMS

KW - OXIDATION

KW - CO

KW - NANOPARTICLES

KW - PERFORMANCE

KW - MN2O3

UR - http://www.scopus.com/inward/record.url?scp=85044627083&partnerID=8YFLogxK

U2 - 10.1039/c7ra11557a

DO - 10.1039/c7ra11557a

M3 - Article

C2 - 35542767

AN - SCOPUS:85044627083

VL - 8

SP - 11598

EP - 11607

JO - RSC Advances

JF - RSC Advances

SN - 2046-2069

IS - 21

ER -

ID: 12282700