Size regime dependent catalysis by gold nanoparticles for the reduction of eosin
Size regime dependent catalysis by gold nanoparticles for the reduction of eosin
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DOI：
10.1021/jp011420t
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发表时间：
2001-09-27
影响因子：
3.3
通讯作者：
Pal, T
中科院分区：
文献类型：
--
作者：
Sau, TK;Pal, A;Pal, T
在这项工作中，我们已经解决了金粒子催化曙红还原的存在下，硼氢化钠。金纳米颗粒的催化活性对于颗粒的不同尺寸状态（尺寸域依赖性）是不同的。已经表明，催化速率的动力学与颗粒尺寸有关（即，表面积质量等）。催化还原动力学研究表明，在平均粒径为10 ~ 46 nm的范围内，对于相同比表面积的不同颗粒，催化还原速率并不随粒径的减小而成正比增加。随着粒径的增大，反应速率先减小，当粒径大于15 nm时，反应速率增大。而且。如果还考虑质量效应，即催化速率是根据每单位表面积的每单位质量来确定的，则在所研究的整个尺寸范围内，所得催化速率福尔斯随着颗粒尺寸的增加而下降。然而，这两种制度的比率不同。光化学制备的种子结合非迭代生长方法用于生产所需尺寸的催化剂颗粒。小种子颗粒通过存在于Triton X-100水溶液介质中的Au（III）离子的UV照射产生。通过紫外-可见分光光度法和透射电镜研究对颗粒进行了表征。通过该方法获得了几乎球形和几乎单分散的金纳米粒子。
In this work we have addressed the gold particle catalyzed eosin reduction in the presence of NaBH4. The catalytic activity of the gold nanoparticles is different for different size regimes (size domain dependent) of the particles, It has been shown that the kinetics of the catalytic rate has a bearing with the particle size (viz., surface area. mass, etc.). The kinetics of catalytic reduction revealed that for the same surface area of different particles, the catalytic rate does not increase proportionately with the decrease in size over the whole range of average diameter from 10 to 46 nm. The rate decreases first with the increase in particle size, and above 15 nm, it increases. Moreover. if the mass effect is also taken into account, that is, catalytic rate is determined in terms of per unit mass per unit surface area, then the resulting catalytic rate falls with the rise in particle size over the whole range of size studied. However, the rate was different for the two regimes. Photochemically prepared seed in conjunction with noniterative growth method was used for producing the catalyst particles of desired size. The small seed particles were produced by the UV irradiation of Au(III) ions present in aqueous Triton X-100 medium. The particles have been characterized by UV-visible spectrophotometric and TEM studies. Almost spherical and nearly monodispersed gold nanoparticles were obtained by this method.