Silver oxygen dosing

M. Kitson, and R.M. Lambert, Basic studies of the oxygen chemistry of silver Oxygen, dioxygen and superoxide on potassium-dosed Ag(100), Surf. Sci. 109, 60-74 (1981). 

Due to the accurate knowledge of the dose used, a control of the progressive extent of the radiolytic reduction was achieved. However, quite often, puzzling data were reported when the zero-valent metal was formed, such as an induction time for precipitation, a sensitivity of the radiolytic yields to the initial presence of added particles, and an unusually weak reproducibility [9,10]. Moreover, oxidation of silver atoms by molecular oxygen was observed [7], although the process was thermodynamically improbable for a noble metal such as silver. 

Atkins and co-workers studied the detailed kinetics of the adsorption of oxygen on a Ag/a-AhOs catalyst prepared from a silver oxalate precursor [3,11]. They found two states in the oxygen desorption spectrum at 523 K (250 °C) and 573 K (300 °C) (designated hereafter as the aj and czv states, respectively) after having dosed pure O2 (1 bar) for 1 h on to the catalyst which was held at 513 K (240 °C). The high-temperature state was lost on heating to 773 K (500 °C) for the first desorption, but the low-temperature state was imaffected by this heating (Fig. 7.1). 

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