A series of perovskite-type manganites AMnO3 (A = Sr, La, Ca and Y) particles were investigated as electrocatalysts for the oxygen reduction reaction. AMnO3 materials were synthesized by means of an ionic-liquid method, yielding phase pure particles at different temperatures. Depending on the calcination temperature, particles with mean diameter between 20 and 150 nm were obtained. Bulk versus surface composition and structure are probed by X-ray photoelectron spectroscopy and extended X-ray absorption fine structure. Electrochemical studies were performed on composite carbon-oxide electrodes in alkaline environment. The electrocatalytic activity is discussed in terms of the effective Mn oxidation state, A:Mn particle surface ratio and the Mn-O distances.
Keyphrases
- room temperature
- ionic liquid
- high resolution
- dual energy
- metal organic framework
- reduced graphene oxide
- air pollution
- photodynamic therapy
- gold nanoparticles
- single molecule
- solid state
- transition metal
- atomic force microscopy
- computed tomography
- protein kinase
- molecular dynamics simulations
- magnetic resonance
- high efficiency
- mass spectrometry
- anaerobic digestion
- carbon nanotubes