SPECTROSCOPIC INVESTIGATIONS OF GOLD SURFACES

A detailed spectroscopic investigation has been made of carbon monoxide adsorption on supported gold. It is shown that carbon monoxide is weakly, and reversibly, chemisorbed. The effects of too low a reduction temperature of the gold are discussed. Supported gold has been found to dissociate hydrogen (and deuterium) at room temperature, and as a result, the hydroxyl groups of the silica support can be converted into deuteroxy groups with deuterium. Studies have also been made of the oxidation of carbon monoxide over gold by spectroscopic means. Strong chemisorption of either carbon monoxide or oxygen does not occur on gold surfaces, as both gases must be present in the gas phase for carbon monoxide oxidation to occur. Adsorption isotherms of carbon monoxide and hydrogen have been measured on the supported gold systems. About ten times less hydrogen is adsorbed, at a given pressure, than carbon monoxide. With the use of the isotherm data, an approximate extinction coefficient has been calculated for carbon monoxide adsorbed on gold. © 1969.