Electrochemical Promotion Of Catalysis (EPOC) or Non-faradaic Electrochemical Modification of Catalytic Activity (NEMCA)

Phenomenon that refers to the very pronounced and reversible enhancement in catalytic activity and selectivity of metal or metal-oxide catalysts deposited on solid electrolytes caused by application of small electrical currents or potentials

• NO_x reduction from lean-burn and Diesel engine exhaust

Burning fuels either fossil (natural gas, oil, diesel etc.) or fuel produced from sustainable sources (bio-fuel), generates pollutants like nitrogen oxides (NO_x), which need to be destroyed before they can reach the atmosphere. Two types of NO_x sources can be distinguished due to human activities: stationary and automotive emissions. The first are attributed to the factories producing nitrous compounds or to industries where the chemical or thermal processes lead to oxidation of the nitrogen contained in air.

Reduction of pollutant emissions present in the exhaust of lean-burn and Diesel engines has attracted great scientific interest due to a recent strategy to improve fuel efficiency (and thus reduce overall emissions). However, the high oxygen concentration hinders the NO_x reduction reaction in the catalytic converter, making necessary the implementation of a transient NO_x storage process and continuous shifting of the engine operation between lean-burn and rich-burn conditions. The phenomenon of Electrochemical Promotion of Catalysis combined with classical heterogeneous catalysis could be applied for catalyst regeneration and activation during NO_x reduction in excess of oxygen.

• Reactor development for practical application of Electrochemical Promotion

Efficient, compact and intelligent reactor designs must be utilized to make an electrochemically promoted reactor commercially attractive

Evolution of cell configurations for EPOC

(Group of Electrochemical Engineering - GGEC, EPFL)

• Design of catalytic systems in nanometer range and their application to EPOC

Rh catalyst (40 nm) sputtered Rh catalyst (40 nm) sputtered on TiO₂

on Yttria-Stabilized Zirconia (YSZ)