STTR Phase I: Spray-On Nanostructured Metal Oxide Films for Efficient Solar Energy Conversion

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). This Small Business Technology Transfer Research Phase I project exploits Inframat's revolutionary solution plasma spray process to fabricate nanostructured dendritic oxide films for low cost photovoltaic solar energy or solar/water hydrogen splitting device applications. High surface area metal oxide films are crucial device elements for next generation energy conversion. While much fundamental work has been conducted to demonstrate feasibility and build prototypes, little progress has been made towards addressing the cost and reliability of efficient, high rate manufacturing processes for these devices. Our process, developed through collaboration between Inframat and UMass, involves the deposition of oxide films via the introduction of a fine aerosol produced by the rapid expansion of precursor solutions saturated with a compressible solvent into a plasma spray gun. Our feasibility experiments indicate that the process yields open, highly porous networks of dendritic oxide nanostructures directly, without subsequent casting or annealing steps. The intellectual merit includes the development of a deposition technology for pure/doped nanofilms that offers well controlled architectures and the establishment of the relationships between deposition conditions, precursor reactivity and film properties. Performance comparison of solar cells constructed using these materials to baseline devices of traditional film approaches will provide additional understanding of structure-property relationships. The broader impact includes validation of an inexpensive, manufacturable, spray on route to nanostructured metal oxide films that could significantly reduce the cost of solar cells and H2 generation. The technology is applicable to other devices, including sensors and batteries. The anticipated benefits/potential commercial applications include robust processing, high quality and performance, and economical affordability for next generation energy conversion devices. The spray on nature of SPS processing allows us to target the low cost, large area segment of the market, which is currently underrepresented due in part to high manufacturing costs relative to efficiency. The ability to tune film structure and crystallinity at the nanoscale offers enabling gains in device performance and efficiency. The customers include both large and small companies in the solar energy space, including those with a concentrated focus on dye-sensitized and flexible solar cells.