SBIR Phase I: Dynamic Infared Filter of Vanadium Oxide Window Films for Improved Energy Efficiency

This Small Business Innovation Research (SBIR) Phase 1 project focuses on commercialization of stimuli responsive metal-insulator transitions in binary and ternary vanadium oxides. The remarkable tunability of the transition upon incorporation of substitutional and/or interstitial dopant ions has filled a key technological gap for their deployment as a dynamic infrared filter in thermally switchable laminates for fenestration (windows, doors, and skylights) and automobile glass. Much of the solar heat gain in structures occurs from the transmission of infrared energy (heat) through poorly insulating glass units. The stimuli responsive window laminates have several unique features to improve insulating glass units including: thermally switchable heat-blocking to heat-transmitting metal-insulator phase changes (or vice versa) without a substantial change in visible transmittance, adjustment of the transition temperature to meet the needs of different climatic regions, and incorporation of the nanomaterials into a flexible polymer matrix for high-end roll-to-roll retrofittable window laminates. The combination of this unique feature set enables our stimuli responsive window laminates to mitigate air-conditioning costs during warmer months while allowing the sun?s natural solar energy to warm interior spaces during cooler months without adversely affecting visible transparency. The broader impact/commercial potential of this project is in using switchable window laminates to address critical needs in energy inefficient and outdated buildings, where more than 85% of buildings that exist today will exist in 20 years. This represents a relatively underutilized served market of size of $3.4 billion in the U.S. Much of the recent focus on energy efficiency relates to new buildings and deep renovations; yet the overwhelmingly poor energy efficiency of outdated buildings necessitates a facile low-cost retrofittable solution to reduce energy consumption and carbon dioxide emissions in the U.S. Our stimuli responsive laminates address this need and will contribute to U.S. competitiveness in green building materials and energy efficiency. The long term society impact will be more energy efficient buildings with a reduced carbon footprint, particularly in existing buildings.