Mackus Adriaan J M, Weber Matthieu J, Thissen Nick F W, Garcia-Alonso Diana, Vervuurt René H J, Assali Simone, Bol Ageeth A, Verheijen Marcel A, Kessels Wilhelmus M M
Department of Applied Physics, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands.
Nanotechnology. 2016 Jan 22;27(3):034001. doi: 10.1088/0957-4484/27/3/034001. Epub 2015 Dec 4.
The deposition of Pd and Pt nanoparticles by atomic layer deposition (ALD) has been studied extensively in recent years for the synthesis of nanoparticles for catalysis. For these applications, it is essential to synthesize nanoparticles with well-defined sizes and a high density on large-surface-area supports. Although the potential of ALD for synthesizing active nanocatalysts for various chemical reactions has been demonstrated, insight into how to control the nanoparticle properties (i.e. size, composition) by choosing suitable processing conditions is lacking. Furthermore, there is little understanding of the reaction mechanisms during the nucleation stage of metal ALD. In this work, nanoparticles synthesized with four different ALD processes (two for Pd and two for Pt) were extensively studied by transmission electron spectroscopy. Using these datasets as a starting point, the growth characteristics and reaction mechanisms of Pd and Pt ALD relevant for the synthesis of nanoparticles are discussed. The results reveal that ALD allows for the preparation of particles with control of the particle size, although it is also shown that the particle size distribution is strongly dependent on the processing conditions. Moreover, this paper discusses the opportunities and limitations of the use of ALD in the synthesis of nanocatalysts.
近年来，通过原子层沉积（ALD）法沉积钯和铂纳米颗粒已被广泛研究，用于催化纳米颗粒的合成。对于这些应用而言，在大表面积载体上合成尺寸明确且高密度的纳米颗粒至关重要。尽管已经证明了ALD在合成用于各种化学反应的活性纳米催化剂方面的潜力，但仍缺乏关于如何通过选择合适的工艺条件来控制纳米颗粒性质（即尺寸、组成）的深入了解。此外，对于金属ALD成核阶段的反应机理了解甚少。在这项工作中，通过透射电子光谱对用四种不同ALD工艺（两种用于钯，两种用于铂）合成的纳米颗粒进行了广泛研究。以这些数据集为起点，讨论了与纳米颗粒合成相关的钯和铂ALD的生长特性和反应机理。结果表明，ALD能够在控制粒径的情况下制备颗粒，不过也表明粒径分布强烈依赖于工艺条件。此外，本文还讨论了在纳米催化剂合成中使用ALD的机遇和局限性。
