We report that TiO 2 coatings formed via atomic layer deposition (ALD) may tune the activity of IrO 2 , RuO 2 , and FTO for the oxygen-evolution and chlorine-evolution reactions (OER and CER). Electrocatalysts exposed to ~3-30 ALD cycles of TiO 2 exhibited overpotentials at 10 mA cm -2 of geometric current density that were several hundred millivolts lower than uncoated catalysts, with correspondingly higher specific activities. For example, the deposition of TiO 2 onto IrO 2 yielded a 9-fold increase in the OER-specific activity in 1.0 M H 2 SO 4 (0.1 to 0.9 mA cm ECSA -2 at 350 mV overpotential). The oxidation state of titanium and the potential of zero charge were also a function of the number of ALD cycles, indicating a correlation between oxidation state, potential of zero charge, and activity of the tuned electrocatalysts.
ASJC Scopus subject areas
- Environmental Chemistry
- Renewable Energy, Sustainability and the Environment
- Nuclear Energy and Engineering