Electrocatalytic Modification of Indium Tin Oxide Electrode Surfaces: Surface Analyses and Electrochemistry

Abstract

Electrochemical data and surface analyses are presented for ‐ and Pt‐modified surfaces of indium tin oxide (ITO) electrodes. The goal of this study was to combine the excellent optical transparency of this material with good catalytic activity. Spray pyrolysis was used to develop islands on the ITO electrode surface. Platinum was deposited by spray pyrolysis and electrodeposition. Unlike the ring‐like morphology obtained with , both methods yielded dense Pt clusters on the ITO surface. In all these cases, the good optical transparency of ITO was not compromised even at relatively high catalyst loads. For example, even at the maximal catalyst loadings in these experiments, the electrodes showed ∼50% light transparency. Detailed surface characterizations were carried out on these catalyst‐modified ITO surfaces using scanning electron microscopy, profilometry, scanning Auger microscopy, Auger electron spectroscopy, and x‐ray photoelectron spectroscopy. Electrochemical data for ‐ and Pt‐modified ITO electrodes are presented for the oxygen evolution, hydrogen evolution, and bromide oxidation reactions and compared with the behavior of the virgin material. Finally, an electrochemical method is described for assaying the Ru content of the ITO surface. This method yields results with an approximately one‐to‐one correspondence with the Ru content estimated from the Auger electron spectroscopy data.