Efficient Removal of Organic Ligands from Supported Nanocrystals by Fast Thermal Annealing Enables Catalytic Studies on Well-Defined Active Phases

Abstract

A simple yet efficient method to remove organic ligands from supported nanocrystals is reported for activating uniform catalysts prepared by colloidal synthesis procedures. The method relies on a fast thermal treatment in which ligands are quickly removed in air, before sintering can cause changes in the size and shape of the supported nanocrystals. A short treatment at high temperatures is found to be sufficient for activating the systems for catalytic reactions. We show that this method is widely applicable to nanostructures of different sizes, shapes, and compositions. Being rapid and effective, this procedure allows the production of monodisperse heterogeneous catalysts for studying a variety of structure-activity relationships. We show here results on methane steam reforming, where the particle size controls the CO/CO2 ratio on alumina-supported Pd, demonstrating the potential applications of the method in catalysis.

Base metal-Pt alloys: A general route to high selectivity and stability in the production of biofuels from HMF

“…The supernatant was removed and the precipitate was washed twice with isopropanol, followed by centrifugation. After drying each sample in a vacuum oven overnight at 50 °C, the samples were first treated with an O 2 plasma cleaner (18 W, Harrick Plasma) for 15 min, then transferred for 1 min into a muffle furnace that had been preheated to 500 °C [21].…”

Ligand-Free Noble Metal Nanocluster Catalysts on Carbon Supports via “Soft” Nitriding

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Engineering of Ruthenium–Iron Oxide Colloidal Heterostructures: Improved Yields in CO2 Hydrogenation to Hydrocarbons

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