Formation of Iridium(IV) Oxide (IrO<sub><i>X</i></sub>) Films by Electroflocculation
- Publication date
- Publisher
Abstract
Films
of iridium(IV) oxide nanoparticles (IrO<sub><i>X</i></sub> NPs) become deposited on electrodes from nanoparticle solutions
when potentials sufficient to initiate water oxidation are applied.
Evidence is given that the film-forming mechanism is nanoparticle
precipitation. Following an induction period during which a significant
amount of charge is passed, the NPs begin to deposit as islands. It
appears that the proton release that accompanies nanoparticle oxidation
triggers the nanoparticle electroflocculation and subsequent precipitation.
Flocculation from nanoparticle solutions can also be induced by the
addition of a chemical oxidant (Ce(IV)). The film formation is followed
by cyclic voltammetry (CV), rotated ring disk voltammetry (RRDE),
and electrochemical quartz crystal microbalance (eQCM) measurements,
supplemented with AFM and SEM microscopies