Wang Haifeng君が中心となって行った村山先生との共同研究の成果がACS Catalysis (ACS)にAcceptされました。Our collaboration with Prof. Murayama was published in ACS Catalysis (ACS).
「Understanding the distinct effects of Ag nanoparticles and highly dispersed Ag species on N<sub>2</sub> selectivity in NH3-SCO reaction」Wang, Haifeng; Murayama, Toru; Lin, Mingyue; Sakaguchi, Norihito; Haruta, Masatake; Miura, Hiroki; Shishido, Tetsuya
ACS Catalysis, 2022, 12, 6108-6118. DOI: 10.1021/acscatal.1c05762
Ag-based catalysts, especially Ag/Al2O3, show high NH3 oxidation activity in NH3-selective catalytic oxidation (NH3−SCO). However, the low N2 selectivity limits their further application. To improve N2 selectivity, herein, a series of Ag/Al2O3-X catalysts (X = calcination temperature) are designed by simple calcination. Only Ag nanoparticles (Ag NPs) were observed on the Ag/ Al2O3-400 catalyst, while highly dispersed Ag species (Ag HDs) were dominated on the Ag/Al2O3-800 catalyst. NH3−SCO results showed that Ag NPs/Al2O3 forms much N2O by-products, whereas Ag HDs/Al2O3 achieves >99% N2 selectivity over the Ag/Al2O3-800 catalyst at <200 °C. More importantly, various intermediates (NO3 ads, NH2 ads, NN−M, and NN−O−M) and their internal transformations were detected, and the reaction pathways for the formation of N2O and N2 are evidenced by in situ NH3-Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). This study not only provides a convenient and effective approach to obtain excellent N2 selectivity in NH3−SCO but also affords a systematic insight into the reaction pathways over Ag/Al2O3 catalysts.