Performance of titanium oxynitrides in the electrocatalytic oxygen evolution reaction

摘要: Abstract We report results of a detailed study on the activity and stability titanium oxynitrides in oxygen evolution reaction (OER) their correlation with structure (surface) composition these materials, which had been reported as promising catalysts for this reverse reduction (ORR). Combining electrochemical flow cell measurements online mass spectrometry analysis (differential spectrometry) allows us to separate catalytic O2 from other reactions such catalyst oxidation. Materials different nitridation levels were fabricated via thermal treatment oxide gaseous ammonia. The resulting cover wide range O:N ratios, characterized by X-ray diffraction, elemental carbon-hydrogen-nitrogen analysis, photoelectron spectroscopy, yielding information about bulk crystallinity, chemical composition, surface species present, respectively. They show increasing oxidation current densities starting at 1.2 V, peak maximum 1.7 V. Online however, reveals that electrode rather than evolution, while occurs only potentials >1.7 V. Increasing nitride contents found increase reaction, onset is independent extent nitridation. Consequences findings suitability materials OER will be discussed.