In Situ Tuning of Catalytic Activity by Thermoelectric Effect for Ethylene Oxidation

The use of the thermoelectric material BiCuSeO as a support and promoter for catalytic ethylene oxidation is reported here. The catalytic activity of a continuous and noncontinuous Pt catalyst supported on BiCuSeO was observed to be promoted significantly by an in situ generated thermoelectric Seebeck voltage by the temperature difference across the material. It has also been shown that this promotion of catalysis by the thermoelectric effect enabled the material BiCuSeO itself to be highly catalytically active for ethylene oxidation. A linear relationship between the logarithm of the reaction rate and the thermoelectric Seebeck voltage was also observed. The thermoelectric promotion of catalysis is attributed to the change of work function of the catalyst surface, accompanied by a charge transfer from the bulk to the surface that is caused by the thermoelectric effect.