Kumar Sachin, Zou Shouzhong
Department of Chemistry and Biochemistry, Center for Nanotechnology, Miami University, Oxford, Ohio 45056, USA.
J Phys Chem B. 2005 Aug 25;109(33):15707-13. doi: 10.1021/jp051981a.
Gold nanoparticles were attached to amine-functionalized indium tin oxide substrate to form particle ensemble electrodes with controlled particle coverage. Electrooxidation of carbon monoxide (CO) on these particle ensemble electrodes was studied in CO-saturated alkaline solutions by means of cyclic voltammetry, with an emphasis on the effects of particle coverage. CO oxidation half-wave potential was found to decrease with increasing particle density. However, the current density was significantly larger at lower particle coverage electrodes. On the basis of a model for electron transfer on a partially covered electrode, the observations were explained in terms of the change in reactant mass transport pattern with varying particle coverages: CO diffusion is predominantly mixed spherical and linear at low particle coverages and changes to mostly linear at high particle coverages. The possibility of contributions from particle agglomeration is also briefly discussed.
金纳米颗粒附着在胺功能化的铟锡氧化物基底上，以形成具有可控颗粒覆盖率的颗粒集合电极。通过循环伏安法研究了这些颗粒集合电极上一氧化碳（CO）在CO饱和碱性溶液中的电氧化，重点关注颗粒覆盖率的影响。发现CO氧化半波电位随颗粒密度的增加而降低。然而，在较低颗粒覆盖率的电极上电流密度明显更大。基于部分覆盖电极上电子转移的模型，根据反应物质量传输模式随颗粒覆盖率变化的情况对这些观察结果进行了解释：在低颗粒覆盖率下，CO扩散主要是混合球形和线性的，而在高颗粒覆盖率下变为主要是线性的。还简要讨论了颗粒团聚产生影响的可能性。
