Nanoparticles of metal and metal oxides: some peculiar synthesis methods, size and shape control, application to catalysts preparation

Abstract

One step (direct) and multisteps synthesis methods of metal and oxide nanoparticles are presented including both bottom-up and top-down procedures. Chemical methods involving the polyol process allows to get either isotropic or anisotropic nanoparticles. Nanowires, nanorods and dumbells can be generated either by heterogeneous nucleation or by using a template (mesoporous silica). Top-down procedures are illustrated by laser irradiation of immersed bulk targets (Ag, Au) which generates self-organized nanostructures or colloidal solutions. Laser irradiation of these colloidal solutions modifies the size distribution and the shape of nanoparticles. Bimetallic nanoparticles are generated from mixtures of monometallic colloidal solutions. Surface-mediated methods involving a host support and an invited phase are also presented. They lead to the formation of metal or oxide clusters and nanoparticles. The speciation of these entities is correlated with the observed catalytic performances.

Effects of the microwave heating on the properties of gadolinium-doped cerium oxide prepared by polyol method

“…Table 3 Activation energies for bulk and grain boundary conduction in the low temperature range and total activation energies in the 250-800 • C range. 20. Activation energies for bulk and grain boundary conduction in the low temperature range and total activation energies in the 250-800 • C range.…”

“…[16][17][18] Polyol mediated method has been recently used 19 to synthesize powders of different metals and high purity mixed oxides. 20 With this method, fine particles are formed by heating their precursor salts in high boiling alcohols (e.g. ethylene glycol, diethylene glycol, etc.).…”

An Efficient One‐pot Synthesis of 2‐Amino‐5‐arylidenethiazol‐4‐ones Catalyzed by MgO Nanoparticles

“…Metal oxide nanoparticles have been found excellent applications as catalysts in the synthesis of organic compounds. [23][24][25] Their high reactivity is due to their limited size and a high density of corner or edge surface sites. 26,27 Among them, magnesium oxide nanoparticle (MgO-NPs) is most widely used as heterogeneous catalyst and exhibits high activities in numerous base-catalyzed organic reactions.…”

Creating and mastering nano-objects to design advanced catalytic materials

“…There are various synthesis strategies to prepare 1D-type metal oxide nanomaterials (e.g., nanorods, nanowires, and nanotubes) [142,143]. Vapour phase methods, such as physical or chemical vapour phase deposition have often been used to prepare metal oxide nanorods of V, Zn, Fe, Ti and other metals [142,144,145].…”