Investigation of Reaction Mechanism of NO–C(3)H(6)–CO–O(2) Reaction over NiFe(2)O(4) Catalyst

[Image: see text] To elucidate the reaction mechanism of NO–C(3)H(6)–CO–O(2) over NiFe(2)O(4), we investigated the dynamics of the adsorbed and gaseous species during the reaction using operando Fourier transform infrared (FTIR). The NO reduction activity dependent on the C(3)H(6) and CO concentrations suggested that NO is reduced by C(3)H(6) under three-way catalytic conditions. From FTIR measurements and kinetic analysis, it was clarified that the acetate species reacted with NO–O(2) to form N(2) via NCO, and that the rate-limiting step of NO reduction was the reaction between CH(3)COO(–) and NO–O(2). The NO reduction mechanism of the three-way catalyst on NiFe(2)O(4) is different to that on platinum-group metal catalysts, on which NO reduction proceeds through N–O cleavage.