Reactive Electrophilic O^I- Species Evidenced in High-Performance Iridium Oxohydroxide Water Oxidation Electrocatalysts.

ABSTRACT: Although quasi-amorphous iridium oxohydroxides have been identified repeatedly as superior electrocatalysts for the oxygen evolution reaction (OER), an exact description of the performance-relevant species has remained a challenge. In this context, we report the characterization of hydrothermally prepared iridium(III/IV) oxohydroxides that exhibit exceptional OER performances. Holes in the O 2p states of the iridium(III/IV) oxohydroxides result in reactive O^I- species, which are identified by characteristic near-edge X-ray absorption fine structure (NEXAFS) features. A prototypical titration reaction with CO as a probe molecule shows that these O^I- species are highly susceptible to nucleophilic attack at room temperature. Similarly to the preactivated oxygen involved

SUBMITTER: Massue C 

PROVIDER: S-EPMC5813174 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature