Cathodic deposition of molybdenum and vanadium mixed oxyhydroxide films from V-substituted polymolybdophosphate

Creators Nakayama Masaharu

Creators Komatsu Hiroyuki

Creators Ozuka Shotaro

Creators Ogura Kotaro

We report a new electrochemical route for fabricating molybdenum and vanadium mixed oxyhydroxide films on Au electrode from Keggin-type vanadium-substituted polymolybdophosphate. The process involves a potentiodynamic reduction of aqueous 9-molybdo(VI)-3-vanadophosphosphate(V) ([Pmo_9V_3O_<40>]^<6->) in the potential region between 0 and -0.7 V versus Ag/AgCl. The resulting MoV oxyhydroxide film electrode gave a stable redox behavior in Na_2SO_4 electrolyte of pH 3. X-ray photoelectron spectroscopy revealed that this results from oxidation/reduction of Mo^<5+>/Mo^<6+> in the film which accompanies extraction/insertion of protons for charge compensation. The deposited V ions remained in the film upon repetitive potential cycling without affecting their oxidation state. Voltammetric data in the presence of sodium nitrite showed electrocatalytic activity of the Mo-V oxyhydroxide toward the electroreduction of nitrite.

[ISSN]0013-4686

[NCID]AA00633261

https://doi.org/10.1016/j.electacta.2005.04.025

[isVersionOf] [URI]http://www.sciencedirect.com/science/journal/00134686