Broader Impacts

1. Photocatalytic Water Splitting by Platinum Loaded Carbon Doped Cadmium Indate NanoparticlesMichael D. Raftery, Purdue University, DMR 0805096 B A Due to the rising concern over dwindling fuel resources and the environmental impact of fossil fuels, alternative energy sources are required. Hydrogen fuel produced through the process of solar water splitting is a promising approach. Hydrogen fuel can provide electricity via a fuel cell and burns cleanly such that the output is only water without additional CO2. We are investigating a new catalyst, carbon doped cadmium indate, C-CdIn2O4 for solar hydrogen production. When placed in an aqueous solution and irradiated with UV-visible light our catalyst is capable of splitting water and producing hydrogen gas. Fig. 1A. shows the hydrogen generation rate of indium based catalysts C-CdIn2O4, CdIn2O4, and C-In2O3 with different platinum co-catalyst loadings. Both of the Cd containing samples showed an optimal loading of 0.25% (w/w) while the C-In2O3 showed an optimal loading of 0.20% (w/w). The H2 production plots for C-CdIn2O4, CdIn2O4, C-In2O3, and CdO are compared in Fig. 1B. Plots for TiO2 in water and 10% H2O:MeOH (v/v) are also displayed for comparison. All In-containing materials were measured using the optimized platinum loading amount while CdO used 0.25% and TiO2 used 0.30% (w/w). Pt-loaded CdIn2O4 when doped with carbon showed a higher H2 generation rate (22,000 μmol hr-1 g-1) compared to the undoped catalyst (10,500 μmol hr-1 g-1). The rate for the C-doped material was approximately 4-fold higher than Pt-TiO2, and did not require a sacrificial agent. C-doped CdIn2O4 is a promising metal oxide photocatalyst for solar water splitting. Figure 1. (A) Platinum cocatalyst loading plot (by mass) and (B) Comparison of hydrogen generation plots for various photocatalytic materials. All indium containing materials were measured using the optimized platinum loading amount. (▲) C-CdIn2O4, (■) CdIn2O4, (●) C-In2O3, (◆) CdO (*) TiO2 and (X) TiO2 suspended in a 10% (v/v) H2O:MeOH solution.

2. Photocatalytic Water Splitting by Platinum Loaded Carbon Doped Cadmium IndateNanoparticles Michael D. Raftery, Purdue University, DMR 0805096 Broader Impacts Undergraduate researchers are introduced to solar water splitting research by working closely with graduate students to gain research experience and develop laboratory skills and practices. They learn to synthesize semiconducting metal oxide photocatalytic thin films electrodes by spray pyrolysis and doctor blading as well as evaluation of the materials using photoelectrochemical techniques. The experience they gain will help prepare them for future studies in graduate school or industry careers. Undergraduate researcher Jinhyun Kim Undergraduate researcher setting up a electrode for photoelectrochemical analysis