Morphology-dependent nanocatalysis: metal particles

Abstract

The rapid development of materials science now enables tailoring of metal and metal oxide particles with tunable size and shape at the nanometre level. As a result, nanocatalysis is undergoing an explosive growth, and it has been seen that the size and shape of a catalyst particle tremendously affects the reaction performance. The size effect of metal nanoparticles has been interpreted in terms of the variation in geometric and electronic properties that governs the adsorption and activation of the reactants as well as the desorption of the products. At the same time, it has been verified that the morphology of a catalyst particle, determined by the exposed crystal planes, also considerably affects the catalytic behavior. This is termed as morphology-dependent nanocatalysis: a catalyst particle with an anisotropic shape alters the reaction performance by selectively exposing specific crystal facets. This perspective article initially surveys the recent progress on morphology-dependent nanocatalysis of precious metal particles to emphasise the chemical nature of the morphology effect. Then, the fabrication of transition metal particles with controllable size/morphology is examined, and their shape is correlated with their catalytic properties, with the aim to clarify the structure-reactivity relationship. Finally, the future outlook presents our personal perspectives on the concept of morphology-dependent nanocatalysis of metal particles, which is a rapidly growing topic in heterogeneous catalysis.

Understanding the Role of Solvation Forces on the Preferential Attachment of Nanoparticles in Liquid

“…for ethene oxidation). 4 Desirable properties of nanoparticles utilized in these applications stem from particle size and morphology (e.g. nanorod shapes are preferred for certain applications).…”

“…nanorod shapes are preferred for certain applications). [4][5][6][7] To obtain optimal properties, it is necessary to carefully control particle features during synthesis and ensure stability during use. 8 Particle coalescence is usually to be avoided due to its elimination of accessible particle surface area, but it can also be used to synthesize a desired particle network.…”

The impacts of nanotechnology on catalysis by precious metal nanoparticles

“…For example, with regard to the Fe catalyst for ammonia synthesis, the (111) surface was found to be most active, and the order of reaction rate follows (111) > > (110) > (100) [7,8] . The availability of shape-controlled metal nanocrystals in recent years has provided some exciting opportunities for catalytic studies [9] .…”

“…In a recent review, Koper discussed the special role of two types of active sites on nanoparticle surfaces for electrocatalytic reactions, including (i) steps/ defects in the {111} terraces or facets and (ii) the {100} terraces or facets [30] . The shape dependence of metal nanoparticles is of major interest and importance in catalysis [9] . The above examples only provide an introduction to this new exciting direction, and much work remains to be done in the future in terms of the catalytic properties of shaped-controlled nanoparticles.…”

Sonochemical synthesis of CuO nanostructures and their morphology dependent optical and visible light driven photocatalytic properties

“…The controlled synthesis of oxide nano-semiconductors with well-defined morphology at low cost has been attracted much attention since the optoelctronic and catalytic properties are strongly influenced by the size [12] and shape [13,14] which make these oxide nano-semiconductors as a potential candidate for environmental catalytic industries. There are several synthesis routes such as solution based technique [15], hydrothermal [16], microwave [17] and ultrasonics [18] have been developed to prepare well-defined nanostructures with different morphologies.…”