Atomic layer deposition (ALD) as a tool for catalysts surface design and stabilization against sintering

Abstract

Much effort has been devoted to the generation of more sophisticated synthesis methods to obtain particles with as specific composition, size and morphology as possible. In this sense, one of the most promising synthesis techniques is atomic layer deposition (ALD). Unlike conventional methods, ALD allows the generation and growth of precision-controlled atomic-level nanoparticles and films under aspects such as composition, size, thickness and morphology of synthesized particles, that exhibit a high degree of homogeneity in their characteristics. This technique is considered an evolution of the chemical vapor deposition method and is based on self-limiting reactions between gaseous precursors and the solid surface of a chosen substrate, through discrete vapor pulses containing the elements that will constitute the catalyst on the support surface. ALD technique will allow to extend our knowledge related to catalytic selectivity from surface science mechanistic studies, developing catalysts with well-defined characteristics. In this direction will be possible to produce particles with specific geometry, that is, particles with narrow size distributions and well-defined shapes dispersed on high-surface-area silica supports, in order to verify the influence of the surface structure on the selectivity of catalytic reaction. Another possibility that ALD technique offer has been to develop isolate dispersed metal nanoparticles to prevent their sintering during high-temperature reactions. Given this, there is a great interest of our research group of Heterogeneous Catalysis at domain and implementation of this technique and its potentialities, so that high impact works continue to be produced in this area of knowledge. The high-level control using ALD technique allows more accurate and in-depth studies involving the relationship between structural properties and catalytic performance of the materials studied. (AU)