Particle size–activity relationship for CoFe2O4 nanoparticle CO oxidation catalysts

The inverse spinel CoFe2O4 is prepared as nanoparticles with a range of controlled sizes. Synthesis is performed using solvothermal and coprecipitation chemistry, and a two capping group coprecipitation procedure using oxalic acid and ethylenediamine or triethanolamine is shown to afford sub-10 nm, controlled size nanoparticles. A pronounced particle size–activity relationship is observed for CO oxidation catalysis for the studied range of particle sizes. In addition, these unsupported nanoparticle catalysts readily undergo activation during catalysis and exhibit both structural and performance stability under the test reaction conditions.