Surface structure effects in the reactions of nitric oxide with hydrogen and carbon monoxide on rhodium: A comparison with the surface structure effects observed for the hydrogen-oxygen and carbon monoxide-oxygen reactions |
| |
Affiliation: | 1. School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Garden Point Campus, Brisbane, QLD 4001, Australia;2. School of Chemical Engineering, University of Adelaide, Adelaide, SA 5005, Australia;2. Teer Coatings Ltd., West Stone House, Droitwich, United Kingdom;1. School of Chemistry, The University of New South Wales, Sydney, New South Wales, 2052, Australia;2. School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales, 2308, Australia;3. State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China;4. Australian Centre for Advanced Photovoltaics (ACAP), School of Photovoltaic and Renewable and Engineering, University of New South Wales, Sydney, NSW, 2052 Australia;5. Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, China;6. Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China |
| |
Abstract: | Using field electron microscopy (FEM) and thermal desorption and reaction spectroscopy (TDS) the behaviour of various Rh single crystal surfaces towards reactions involving NO has been studied. If, after NO adsorption up to saturation at 77 K, the temperature is slowly raised the FEM results suggest that dissociation of NO starts at the (321), (331) and (533) surfaces. The reaction of NOads with hydrogen starts also at these surfaces (at about 360 K) suggesting that NO bond scission initiates the reaction. After initiation a surface explosion is observed. Depending on the heating rate either a clean surface or a Nads covered surface is obtained after completion of the reaction. Apparently, the reduction of adsorbed Nads by hydrogen can occur at a significant rate at this temperature. At a higher heating rate the formed N adatoms do not react with hydrogen and are readily desorbed as N2 at 600 K. The reaction of NOads with CO starts again on the (321) and (331) surfaces. The rate of the reaction with CO is, however, much lower than that with hydrogen. For the reaction of COads with NO, desorption of CO is the initiation step. The mechanisms of the reactions and the dependence of the reaction on the surface structure are discussed in relation to literature data. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|