1. Solar Hydrogen Project Group Update 25 th August 2009

2. Solar Hydrogen Project Palang Bumroongsakulsawat 25 th August 2009

3. WO 3 in 1M H 2 SO 4

4. WO 3 in 1M H 2 SO 4 : Illuminated (White Light)

5. WO 3 in 1M H 2 SO 4 : Chopped Illumination

6. Photoelectrochemistry Paper(s) “Electrochemical characterisation of Fe 2 O 3 thin- film photoelectrodes” –Impedance analysis (FRA and Mott-Schottky) –Photocurrent transient behaviour –Identification and explanation of the “anomalous” ac photocurrent behaviour Comparison of thin-film WO 3 photoelectrodes by different deposition methods

7. Solar Hydrogen Project Zack Ulissi 25 th August 2009

10. Over PotentialNernst PotentialBand Bending Interface (Anode) Interface (Cathode) Resistance (Solution) Resistance (Membrane)

11. Over PotentialNernst PotentialBand Bending Interface (Anode) Interface (Cathode) Resistance (Solution) Resistance (Membrane)

12. Interface (Anode) Interface (Cathode) Resistance (Solution) Resistance (Membrane) Potentiostat Albery et al. 1996

13. Interface (Anode) Interface (Cathode) Resistance (Solution) Resistance (Membrane) Same Current Density at Anode/Cathode Anode Current Anode Overpotential Cathode Current Cathode Overpotential

14. Interface (Anode) Interface (Cathode) Resistance (Solution) Resistance (Membrane) 0 Single Channel (no membrane) Nernst-Planck Equations, with Electroneutrality, for Na, Cl, H, OH Equilibrium H/OH DiffusionMobilityConvection

15. pH Distribution as a function of potentiostat setting pH V

16. pH Distribution as a function of potentiostat setting V pH

17. Current density along reactor length Current Density, Average Current Density 5 A/m 2 Distance Along Reactor 0.0001 A/m 2

18. Effective I-V Curves Current Density [A/m 2, Potentiostat Voltage (NOT the overpotential!)

19. Next steps Update report with new methods Finish converting work to 3D case (relatively straightfoward, but need faster computers) Double check exiting codes Confirm reactor parameters Add effect of band bending from Mott- Schottky plots Use Buttler-Volmer kinetics for H2 evolution Couple new kinetics with gas evolution

20. Solar Hydrogen Project Chris Carver 25 th August 2009

21. POTENTIOMETER SOLAR SIMULATOR PUMPRESERVOIR / H2 COLLECTION PEC REACTOR PC

25. PHOTOANODE AB