222 research outputs found
Identification of the electroelastic coupling from full multi-physical fields measured at the micrometre scale
Pseudo-single crystal electrochemistry on polycrystalline electrodes : visualizing activity at grains and grain boundaries on platinum for the Fe2+/Fe3+ redox reaction
The influence of electrode surface structure on electrochemical reaction rates and mechanisms is a major theme in electrochemical research, especially as electrodes with inherent structural heterogeneities are used ubiquitously. Yet, probing local electrochemistry and surface structure at complex surfaces is challenging. In this paper, high spatial resolution scanning electrochemical cell microscopy (SECCM) complemented with electron backscatter diffraction (EBSD) is demonstrated as a means of performing ‘pseudo-single-crystal’ electrochemical measurements at individual grains of a polycrystalline platinum electrode, while also allowing grain boundaries to be probed. Using the Fe2+/3+ couple as an illustrative case, a strong correlation is found between local surface structure and electrochemical activity. Variations in electrochemical activity for individual high index grains, visualized in a weakly adsorbing perchlorate medium, show that there is higher activity on grains with a significant (101) orientation contribution, compared to those with (001) and (111) contribution, consistent with findings on single-crystal electrodes. Interestingly, for Fe2+ oxidation in a sulfate medium a different pattern of activity emerges. Here, SECCM reveals only minor variations in activity between individual grains, again consistent with single-crystal studies, with a greatly enhanced activity at grain boundaries. This suggests that these sites may contribute significantly to the overall electrochemical behavior measured on the macroscale
Surface Structure Dependence of Platinum (111), (110), (100)-Hydrogen Systems Studied by Electrochemical Methods
Tellurium Adatoms as an In-Situ Surface Probe of (111) Two-Dimensional Domains at Platinum Surfaces
CYP3–15: An up-promoter mutation at the ISO-2 cytochrome c structural gene locus and its interaction with other independent regulatory mutations of cytochrome c synthesis in Saccharomyces cerevisiae
The overproducing CYP1 and the underproducing hap1 mutations are alleles of the same gene which regulates in trans the expression of the structural genes encoding iso-cytochromes c
Fundamental aspects of HCOOH oxidation at platinum single crystal surfaces with basal orientations and modified by irreversibly adsorbed adatoms
Atomic-Resolution Electrochemical Scanning Tunneling Microscopy: Evidence of I−Pd Place Exchange in the I (Ads)
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