Water Oxidation Catalyzed by Cobalt(II) Adsorbed on Silica Nanoparticles
journal contributionposted on 05.09.2012, 00:00 by Tomer Zidki, Lihua Zhang, Vladimir Shafirovich, Sergei V. Lymar
A novel, highly efficient, and stable water oxidation catalyst was prepared by a pH-controlled adsorption of Co(II) on ∼10 nm diameter silica nanoparticles. A lower limit of ∼300 s–1 per cobalt atom for the catalyst turnover frequency in oxygen evolution was estimated, which attests to a very high catalytic activity. Electron microscopy revealed that cobalt is adsorbed on the SiO2 nanoparticle surfaces as small (1–2 nm) clusters of Co(OH)2. This catalyst is optically transparent over the entire UV–vis range and is thus suitable for mechanistic investigations by time-resolved spectroscopic techniques.