Department of Biomedical Engineering, Washington University, St. Louis, Missouri 63130, USA.
Nano Lett. 2010 Jan;10(1):30-5. doi: 10.1021/nl903062e.
We have evaluated the catalytic properties of Au-based nanostructures (including nanocages, nanoboxes, and solid nanoparticles) using a model reaction based on the reduction of p-nitrophenol by NaBH(4). From the average reaction rate constants at three different temperatures, we determined the activation energy, the entropy of activation, and the pre-exponential factor for each type of Au nanostructure. The kinetic data indicate that the Au-based nanocages are catalytically more active than both the nanoboxes and nanoparticles probably due to their extremely thin but electrically continuous walls, the high content of Au, and the accessibility of both inner and outer surfaces through the pores in the walls. In addition, a compensation effect was observed in this Au-based catalytic system, which can be primarily interpreted by a model based on kinetic regime switching.
我们使用基于硼氢化钠还原对硝基苯酚的模型反应来评估基于金的纳米结构（包括纳米笼、纳米盒和实心纳米颗粒）的催化性能。根据在三个不同温度下的平均反应速率常数，我们确定了每种类型的金纳米结构的活化能、活化熵和指前因子。动力学数据表明，基于金的纳米笼比纳米盒和纳米颗粒具有更高的催化活性，这可能是由于其极薄但连续的电壁、高含量的金以及通过壁上的孔可进入内外表面。此外，在这个基于金的催化体系中观察到了补偿效应，这可以通过基于动力学状态切换的模型来主要解释。
