Catalytic Efficiency of Iron(III) Oxides in Decomposition of Hydrogen Peroxide: Competition Between the Surface Area and Crystallinity of Nanoparticles.

Abstract

Controlled decomposition of FeC2O4·2H2O in air at 175°C allows the simple synthesis of amorphous Fe2O3 nanoparticles and their controlled one-step crystallization to α-Fe2O3 (hematite). Depending on the reaction time, nanopowders differing in surface area and particle crystallinity are prepared. The samples are characterized by XRD, HRTEM, SAED, and 57 Fe Moessbauer spectroscopy, and their catalytic activity in the decomposition of H2O2 is studied. The amorphous nanopowder with the largest surface area shows the lowest catalytic efficiency, while the highest efficiency is achieved with a sample having a significantly lower surface area, exhibiting a prevailing content of crystalline α-Fe2O3 phase. -(HERMANEK, M.; ZBORIL*, R.; MEDRIK, I.; PECHOUSEK, J.; GREGOR, C.; J.

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Porous Flower-like α-Fe2O3 Nanostructure: A High Performance Anode Material for Lithium-ion Batteries

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“…S12) showed that a doublet spectrum appeared after 1 day. According to the hyperfine parameters at room temperature (Table 1), such a doublet was the Mossbauer spectra of Fe 3+ oxides or oxyhydroxides [47][48][49] transfer between adsorbed Fe 2+ and structural Fe oxide occurred in the absence of Fe 0 or other chemicals which can create galvanic cells with structural Fe oxide. It means this spontaneous electron transfer was not driven by potential difference.…”