The present invention provides an electrode which comprises (a) a supporting substrate, and (b) nanoparticle composition comprising optically transparent conductive nanoparticles. In one embodiment, the nanoparticles are selected from tin-doped indium oxide (ITO), fluorine doped tin oxide (FTO), antimony tin oxide (ATO), gallium zinc oxide (GZO), indium zinc oxide (IZO), copper aluminum oxide, fluorine-doped zinc oxide and aluminum zinc oxide (AZO) nanoparticles and combinations thereof. In one embodiment, the electrode further comprises a transition metal catalyst, and the catalyst is absorbed to the surface of the nanoparticles. Another aspect of the invention relates to methods for preparing the electrode described herein which comprises the step of (1) preparing a suspension of nanoparticles; (2) applying the suspension of the nanoparticles to a support substrate; and (3) annealing the supporting substrate with the nanoparticle for a period of time and at a temperature sufficient to produce nanoparticle film on the electrode.
 This invention was made with government support under grant number DE-FG09-06ER15788 awarded by the Department of Energy, Grant No. W911NF-09-1-0426 awarded by Army Research Office, and DE-SC0001011 awarded by UNC EFRC: Solar Fuels and Next Generation Photovoltaics, an Energy Frontier Research Center funded by U.S. DOEBES. The government has certain rights in this invention.