1393
O2 Reduction at Se Modified Surfaces: Characterization by SPM and DEMS
Here, irreversible adsorption of Se on Rh(111) was examined by voltammetric technique. Surface structure characterization of Se modified Rh(111) substrate was achieved using cyclic voltammetry and in situ STM and AFM. STM images also show a roughening starting at step edges for Se adsorption at certain potentials, similar to the roughening transition observed on Au(111) surface for S and Se adsorption [3][4] or As on Pt(111)[5], suggesting the formation of an. Se–Rh intermetallic compound. Results on the effect on oxygen reduction activity will be presented.
It was observed that chalcogenides usually stripped off under fuel cell operating conditions [6] and also electrochemical hydrogen selenide formation at lower potentials [7].Here, we used differential electrochemical mass spectrometery (DEMS) for an additional quantitative characterisation of Se adlayers via reductive desorption on model fcc metal surfaces like [Rh(111), Pt(111) and Au(111)]
References
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