TY - JOUR

T1 - Comprehensive study of O2 and H2O interaction with La0.9Sr0.1ScO3– oxide

AU - Zakharov, Dmitriy M.

AU - Khodimchuk, Anna V.

AU - Ananyev, Maxim V.

AU - Sumnikov, Sergey V.

AU - Smolnikov, Alexsey G.

AU - Farlenkov, Andrei S.

AU - Fetisov, Andrei V.

N1 - his work is partly performed in the framework of the development program «Priority-2030» of the Mendeleev University of Chemical Technology of Russia, the Government Assignment of the Russian Federation No. 122020100324–3 by IHTE UB RAS, and No. 122013100200–2 by IMET UB RAS. The facilities of the Shared Access Center “Composition of Compounds” and Unique Scientific Setup “Isotopic Exchange” of IHTE UB RAS were used. Authors are grateful to Dr. I.A. Bobrikov for HT-NPD study. The authors would like to thank Dr. A.Yu. Stroeva, Dr. N.M. Porotnikova and Dr. M.I. Vlasov for their contributions to the research work.

PY - 2024/5/1

Y1 - 2024/5/1

N2 - In this paper we study the processes of O2 and H2O interaction with La0.9Sr0.1ScO3−δ. Using high temperature neutron powder diffraction (HT-NPD), the evolution of crystal structure and water uptake was investigated in the temperature range 25–700 °C at 21.3 kPa in O2 and O2 + D2O atmospheres. The results of HT-NPD show the influence of the water uptake by La0.9Sr0.1ScO3–δ bulk on the thermal expansion of the material. The kinetics of oxygen surface exchange was studied using pulsed isotope exchange technique. The measurements were carried out in the temperature range 300−900 °C at pO2 = 5.1, 12.2 and 21.3 kPa in dry and humid (pH2O = 2.6 kPa) conditions. For the first time the physical model describing the kinetics of oxygen surface exchange between the mixture of oxygen and water in the gas phase and a solid oxide has been suggested. The model includes following steps: oxygen dissociative adsorption, oxygen incorporation, hydrogen surface diffusion, water adsorption and dissociation. The rate-determining step of the exchange is considered. The influence of O2 humidification on the oxygen surface exchange is discussed.

AB - In this paper we study the processes of O2 and H2O interaction with La0.9Sr0.1ScO3−δ. Using high temperature neutron powder diffraction (HT-NPD), the evolution of crystal structure and water uptake was investigated in the temperature range 25–700 °C at 21.3 kPa in O2 and O2 + D2O atmospheres. The results of HT-NPD show the influence of the water uptake by La0.9Sr0.1ScO3–δ bulk on the thermal expansion of the material. The kinetics of oxygen surface exchange was studied using pulsed isotope exchange technique. The measurements were carried out in the temperature range 300−900 °C at pO2 = 5.1, 12.2 and 21.3 kPa in dry and humid (pH2O = 2.6 kPa) conditions. For the first time the physical model describing the kinetics of oxygen surface exchange between the mixture of oxygen and water in the gas phase and a solid oxide has been suggested. The model includes following steps: oxygen dissociative adsorption, oxygen incorporation, hydrogen surface diffusion, water adsorption and dissociation. The rate-determining step of the exchange is considered. The influence of O2 humidification on the oxygen surface exchange is discussed.

UR - http://www.scopus.com/inward/record.url?partnerID=8YFLogxK&scp=85189033113

U2 - 10.1016/j.surfin.2024.104140

DO - 10.1016/j.surfin.2024.104140

M3 - Article

VL - 48

JO - Surfaces and Interfaces

JF - Surfaces and Interfaces

SN - 2468-0230

M1 - 104140

ER -