Session X27: Invited Session: Physics for Everyone: Innovative Materials for Energy

Water Splitting with Materials and Sunlight

Sun Catalytix has been developing technology for energy storage and the generation of renewable fuels in an ARPA-E sponsored program. The program has focused on the development and deployment of low-cost earth-abundant catalytic materials coupled to light-absorbing semiconductor systems to capture and convert solar energy into chemical species. This talk will focus on recent work done to couple cobalt-based water-oxidation and nickel-based hydrogen evolution catalysts with silicon-based solar cells. The results demonstrate direct wireless coupling of solar collection with catalytic materials and operate in relatively benign conditions at reasonable conversion efficiency. These results suggest development pathways for solar hydrogen generation using catalyzed particulate solar absorbing materials. Such pathways will be discussed as they may offer relevant means to generate solar-derived hydrogen as a cost-effective fuel for the future.   

Advanced materials manufacturing for solar energy

The US has a robust technical roadmap to get to a \$1/W total installed cost with several potential winners in the race. We dominate in the new technology arena and there is a good chance that tomorrow's winning technology will be from the current crop of contenders. One potential breakthrough is Direct Wafer$^{\rm TM}$ a new manufacturing technique to make silicon wafers at a fraction of the traditional cost. Current wafer manufacturing is a multi-step, energy- and capital-intensive process that wastes half of the valuable silicon feedstock. 1366's Direct Wafer technology forms a standard, 156mm multi-crystalline wafer directly from molten silicon in a semi-continuous, efficient, high-throughput process that eliminates silicon waste. Direct Wafer$^{\rm TM}$ cuts the amount of consumables by a factor of four and requires only half the capital per GigaWatt production capacity thus enabling solar to compete successfully with coal generated electricity.   

Genetically Engineered Materials for Biofuels Production

Agrivida, Inc., is an agricultural biotechnology company developing industrial crop feedstocks for the fuel and chemical industries. Agrivida's crops have improved processing traits that enable efficient, low cost conversion of the crops' cellulosic components into fermentable sugars. Currently, pretreatment and enzymatic conversion of the major cell wall components, cellulose and hemicellulose, into fermentable sugars is the most expensive processing step that prevents widespread adoption of biomass in biofuels processes. To lower production costs we are consolidating pretreatment and enzyme production within the crop. In this strategy, transgenic plants express engineered cell wall degrading enzymes in an inactive form, which can be reactivated after harvest. We have engineered protein elements that disrupt enzyme activity during normal plant growth. Upon exposure to specific processing conditions, the engineered enzymes are converted into their active forms. This mechanism significantly lowers pretreatment costs and enzyme loadings ($>$75{\%} reduction) below those currently available to the industry.   

Innovative oxide materials for electrochemical energy conversion

Research in functional materials has progressed from those materials exhibiting structural to electronic functionality. The study of ion conducting ceramics ushers in a new era of ``chemically functional materials.'' This chemical functionality arises out of the defect equilibria of these materials, and results in the ability to transport chemical species and actively participate in chemical reactions at their surface. Moreover, this chemical functionality provides a promise for the future whereby the harnessing of our natural hydrocarbon energy resources can shift from inefficient and polluting combustion - mechanical methods to direct electrochemical conversion. The unique properties of these materials and their applications will be described. The focus will be on the application of ion conducting ceramics to energy conversion and storage, chemical sensors, chemical separation and conversion, and life support systems. Results presented will include development of record high power density (3 kW/kg) solid oxide fuel cells, NO$_{x}$/CO species selective solid-state sensors, high yield membrane reactors, and regenerative life support systems that reduce CO$_{2}$ to O$_{2}$ and solid C.