Ueda Kakuya, Ohyama Junya, Satsuma Atsushi
Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan.
Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Katsura, Kyoto 615-8520, Japan.
ACS Omega. 2017 Jul 5;2(7):3135-3143. doi: 10.1021/acsomega.7b00165. eCollection 2017 Jul 31.
To elucidate the reaction mechanism of NO-CH-CO-O over NiFeO, 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 CH and CO concentrations suggested that NO is reduced by CH under three-way catalytic conditions. From FTIR measurements and kinetic analysis, it was clarified that the acetate species reacted with NO-O to form N via NCO, and that the rate-limiting step of NO reduction was the reaction between CHCOO and NO-O. The NO reduction mechanism of the three-way catalyst on NiFeO is different to that on platinum-group metal catalysts, on which NO reduction proceeds through N-O cleavage.
为阐明NiFeO上NO-CH-CO-O的反应机理，我们使用原位傅里叶变换红外光谱（FTIR）研究了反应过程中吸附物种和气态物种的动力学。依赖于CH和CO浓度的NO还原活性表明，在三元催化条件下NO被CH还原。通过FTIR测量和动力学分析，明确了醋酸根物种与NO-O反应通过NCO形成N，并且NO还原的速率限制步骤是CHCOO与NO-O之间的反应。NiFeO上三元催化剂的NO还原机理与铂族金属催化剂不同，铂族金属催化剂上的NO还原是通过N-O键断裂进行的。
