Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo , Av. Prof. Lineu Prestes, 748, São Paulo, São Paulo 05508-000, Brazil.
School of Materials, The University of Manchester , Manchester M13 9PL, United Kingdom.
ACS Appl Mater Interfaces. 2015 Nov 25;7(46):25624-32. doi: 10.1021/acsami.5b08725. Epub 2015 Nov 16.
In this work, a simple but powerful method for controlling the size and surface morphology of AgAu nanodendrites is presented. Control of the number of Ag nanoparticle seeds is found to provide a fast and effective route by which to manipulate the size and morphology of nanoparticles produced via a combined galvanic replacement and reduction reaction. A lower number of Ag nanoparticle seeds leads to larger nanodendrites with the particles' outer diameter being tunable in the range of 45-148 nm. The size and surface morphology of the nanodendrites was found to directly affect their catalytic activity. Specifically, we report on the activity of these AgAu nanodendrites in catalyzing the gas-phase oxidation of benzene, toluene and o-xylene, which is an important reaction for the removal of these toxic compounds from fuels and for environmental remediation. All produced nanodendrite particles were found to be catalytically active, even at low temperatures and low metal loadings. Surprisingly, the largest nanodendrites provided the greatest percent conversion efficiencies.
在这项工作中，提出了一种简单但强大的方法来控制 AgAu 纳米枝晶的尺寸和表面形态。通过控制 Ag 纳米颗粒种子的数量，可以快速有效地控制通过电替换和还原反应生成的纳米颗粒的尺寸和形态。较少的 Ag 纳米颗粒种子会导致具有更大的纳米枝晶，并且可以在 45-148nm 的范围内调节颗粒的外径。纳米枝晶的尺寸和表面形态被发现直接影响它们的催化活性。具体来说，我们报告了这些 AgAu 纳米枝晶在催化苯、甲苯和邻二甲苯的气相氧化方面的活性，这是从燃料中去除这些有毒化合物以及进行环境修复的重要反应。所有制备的纳米枝晶颗粒都表现出催化活性，即使在低温和低金属负载下也是如此。令人惊讶的是，最大的纳米枝晶提供了最高的转化率效率。
