What are AQCs?
AQCs are clusters of typically 3 to 10 atoms of metal elements such as Ag, Cu & Au, less than 1nm in size, with properties defined by quantum rather than classical mechanics.
Quantum confinement of electrons, absence of crystalline form and the presence of a band gap, results in new and different properties from bulk materials and conventional nanomaterials.
AQCs have size dependent properties, based on the number of atoms per cluster, therefore properties can be controlled and tuned to mimic other bulk materials including conventional semiconductors but without the problems of hole and electron recombination associated with bulk and nano materials.
AQCs as catalysts
AQCs are prepared by industrially scalable wet chemistry methods. With no surfactant or stabilising agents used, AQC can be easily deposited onto typical supports, such as alumina, silica and zirconia used in the catalyst industry. AQC supported catalysts are very stable at temperatures up to 900°C and in the pH range 1-14.
AQCs have been demonstrated to be effective chemical, photo and electro catalysts. As a chemical catalyst, they have been shown to catalyse the oxidation of organo sulfur compounds to sulfate, at room temperature and with only atmospheric oxygen. This patent protected technology has wide applicability in desulfurization of fuels and hydrocarbon feedstocks. Recent results have shown activity for CO oxidation and propene hydrogenation, with many other potential reactions suitable for investigation.
As a photocatalyst, they have been shown to catalyse the formation of hydrogen from water and UV light, and to photocatalyse the oxidation of organic contaminants, with orders of magnitude more efficiency as there is no recombination of holes and electrons. Recent results are showing promise in extending this technology to be effective under visible light.
As an electrocatalyst they have been shown to be effective for oxidation reactions such as alcohol oxidation and hydrogen oxidation reaction (HOR), where the catalytic interaction of hydrogen atoms and clusters has been demonstrated in a very significant fuel cell process, where there are no current efficient catalysts
Through value sharing industrial collaborations, NANOGAP is continuing to develop AQC catalyst technology with many potential areas of interest, including:
Photochemistry – including hydrogen production from water and visible light, artificial photosynthesis, decontamination and self-cleaning surfaces
Hydrotreating and hydrocracking
Chemical synthesis – syngas, methanol, ammonia, dehydrogenation, epoxidation