It was supposed to be straightforward. Create a fuel cell by sticking an electrode in marine sediment and connect it to an electrode in overlying water. Use the fuel cell to persistently generate electrical power from oxidation of organic matter in sediment by oxygen in overlying water to persistently operate an oceanographic instrument. More than 10 years later, the investigation of the mechanism of power generation by such fuel cells still proves to be revealing. Here I will describe some of what we learned including how bacteria can act as immortal electrode catalysts and how they (might) conduct electrons trough thick biofilms, and what the broader -materials- implications may be. BiographyLeonard M. Tender (Lenny) earned his BS in chemistry at the MIT, where his fascination with electrochemistry took root in Mark Wrighton’s laboratory. He subsequently earned a PhD in chemistry at the UNC, Chapel Hill under Royce Murray where his electrochemical tastes were refined by studying modified electrodes. He is presently a branch head in the Center for Bio/Molecular Science and Engineering at the Naval Research Laboratory where he fancies himself a ``microbial electrochemist".

Superconductivity continues to fascinate both at the fundamental mechanism level and for its potential for applications. In fact Onnes came to Chicago in 1913, just two years after discovering superconductivity, with a detailed plan to make a 10 T superconducting magnet! At the centenary it may be worth reflecting on what of Onnes’ vision has worked and what, so far anyway, has not worked. In the achievement column we can put large numbers of superconducting magnets made of Nb-Ti and Nb3Sn, cooled largely by liquid helium and generating fields above 23 T. Such magnets underpin the large MRI industry (1.5-3T), high field NMR (10-23T), and large accelerators like the LHC (up to 8.5T). Both Nb-Ti and Nb₃Sn are well developed conductor materials, now working close to their intrinsic limits and thus not normally discussed at the MRS, where much greater interest is shown in the cuprate high temperature superconductors. The basis of interest is for electric utility applications in temperature and field domains far from the liquid helium range accessible with Nb-base materials. Extraordinary efforts to master these complex materials have been made and great technical successes achieved. And yet, access to the expected markets has proven much harder than expected, to the point that new discoveries like MgB₂, potentially much cheaper but with much less cryogenic advantage, and pnictides with higher T_c than MgB₂ but lesser T_c than the cuprates, even though with much lower anisotropy, sometimes make their claims against cuprates like YBCO. And now too, new programs to discover much higher T_c, perhaps even at room temperature, are underway. Clearly many want new conductor materials with much higher T_c and H_c2 than the isotropic Nb-base materials. Yet dealing with the anisotropy and the poor grain boundary transport of pnictides and cuprates poses tough manufacturing challenges, problems unlikely to be any less significant with new materials. How to develop appropriate strategies for dealing with these complexities will be a major them of my talk.BiographyDavid Larbalestier is Frances Eppes Professor at Florida State University and Chief Materials Scientist at the National High Magnetic Field Laboratory in Tallahassee, FL. He received his PhD from the Department of Metallurgy at Imperial College in 1970. After two years in Switzerland, he returned to the Superconducting Magnet Research Group of the Rutherford Laboratory in England, working for four years on the development of multifilamentary Nb3Sn conductors and magnets, one fruit of which was the first filamentary Nb3Sn NMR magnet, for which he shared a 1978 IR-100 award with an Oxford Instruments Company team. He joined the Materials Science and Engineering Department at the University of Wisconsin in 1976, becoming director of the Applied Superconductivity Center in the College of Engineering in 1991. His group made the definitive studies of the materials processing science of the most widely used superconductor, Niobium Titanium, an achievement recognized by the 1991 IEEE Particle Accelerator Conference Award and by election to Fellowship of the American Physical Society. Professor Larbalestier has been very active in promoting collaborations uniting industry, national laboratory and other university groups, exerting a leadership role in both the Low Temperature and High Temperature Materials Superconductor Communities, achievements recognized by prizes of the IEEE (1991 and 2000) and the Council for Chemical Research (2000) for collaborations on the first HTS conductor material (Bi,Pb)2Sr2Ca2Cu3Ox. His group has been active in all classes of superconducting materials with applications prospects, including Nb3Sn, YBa2Cu3O7-, MgB2, round wire Bi2Sr2CaCu2Ox and the recently discovered pnictides. He was elected to the National Academy of Engineering in 2003 and was a member of the NRC panel (COHMAG) assessing the status and future of high magnetic field science and technology in 2004-2005. He moved to the NHMFL in 2006.

Hydrogen production from water on heterogeneous photocatalysts is one of the attractive candidates to realize a clean and sustainable energy system based on solar energy. We have mainly worked on developing new photocatalytic materials with suitable band gap energies and positions. Among them, some non-oxide materials such as (oxy)nitrides and oxysulfides have been proved to be potential photocatalysts for overall water splitting under visible light. Especially, typical metal-containing oxynitrides, i.e. (Ga_1–xZn_x)(N_1–xO_x) and (Zn_1+xGe)(N₂O_x), become photocatalysts for overall water splitting with proper modifications for H₂ evolution. They are solid solutions of GaN–ZnO and ZnGeN₂–ZnO, respectively. The photocatalytic activities are strongly dependent on the preparation methods as well as the modification methods for H₂ evolution. The available wavelengths of light for these materials are up to about 500 nm. The apparent quantum efficiencies (AQYs) are several %’s at around 400 nm for both photocatalysts. On the other hand, early transition metal-containing (oxy)nitrides such as TaON, and Ta₃N₅ have been proved to have enough potential for overall water splitting, and they are actually stable enough to evolve H₂ and O₂ under visible light up to 600 nm with proper electron donors and acceptors. Some of them have been successfully applied for two-step photoexcitation type systems, with an AQY higher than 6% at 420 nm. In this presentation, recent progress on photocatalytic overall water splitting made by our group will be shown.BiographyKazunari Domen received B.S. (1976), M.S. (1979), and Ph.D. (1982) honors in chemistry from the University of Tokyo. Dr. Domen joined Chemical Resources Laboratory, Tokyo Institute of Technology in 1982 as Assistant Professor and was subsequently promoted to Associate Professor in 1990 and Professor in 1996. He has moved to the University of Tokyo as Professor in 2004. Domen has been working on overall water splitting reaction on heterogeneous photocatalysts to generate clean and recyclable hydrogen. In 1980, he reported NiO-SrTiO₃ photocatalyst for overall water splitting reaction, which was one of the earliest examples achieving stoichiometric H₂ and O₂ evolution on a particulate system. In 2005, he has succeeded in overall water splitting under visible light (λ < 500 nm) on GaN:ZnO solid solution-based photocatalyst. His research interests now include heterogeneous catalysis and materials chemistry, with particular focus on surface chemical reaction dynamics, photocatalysis, solid acid catalysis, and mesoporous materials.