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Updated: Nov 26, 2025
Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Reversible structural transformation and redox properties of Cr-loaded iron oxide dendrites studied by in situ XANES
Hirosuke Matsui1, Nozomu Ishiguro, Youya Suzuki
1Department of Chemistry, Graduate School of Science & Institute for Advanced Science & Integrated Research Consortium on Chemical Science (IRCCS) & the R-ing (Reaction Infography) World Research Unit (B-1), Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan. h-matsui@chem.nagoya-u.ac.jp mtada@chem.nagoya-u.ac.jp.
Abstract:
Cr-Loaded iron oxide with a dendritic crystalline structure was synthesized and the reversible crystalline phase transition during redox cycling of the iron oxide was investigated. X-ray diffraction and transmission electron microscopy analyses revealed that Cr was well dispersed and loaded in the iron oxide dendrite crystals, whose lattice constant was dependent on the Cr loading. Temperature-programmed oxidation and reduction experiments revealed the reversible redox properties of the Cr-loaded iron oxide dendrites, whose redox temperature was found to be lower than that of Cr-free iron oxide dendrites. In situ Fe K-edge and Cr K-edge X-ray absorption near-edge structure (XANES) analysis indicated that Cr loading extended the redox reaction window for conversion between Fe3O4 and γ-Fe2O3 owing to compressive lattice strain in the iron oxide spinel structures.
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