Self-Cleaning Surfaces with Morphology Mimicking Superhydrophobic Biological Surfaces

76104S The development of self-cleanings windows and other surfaces could lead to significant energy savings. Unfortunately, current state-of-the-art solutions have a number of shortcomings: low clarity, poor abrasion resistance, and insufficient weatherability. This project will develop low cost, high perfomance, self-cleaning coatings based on the superhydrophobic nature of the lotus leaf. Two proprietary processes, Combustion Chemical Vapor Deposition (CCVD) and NanoSpray technology, will be utilized to synthesize nanostructured surfaces, which will demonstrate improved performance at a much reduced manufacturing cost. Phase I investigated the critical process parameteres for the fabrication of the selected materials system. Excellent material and physical properties were achieved, including optical haze less than 0.5%, water contact angle higher than 165 degrees, and water rolling angle less than 5 degree. In Phase II, the process parameters will be fine-tuned to further improve the film's properties, with a shift in focus from laboratory measured properties (hydrophobicity) to field tested properties (abrasion resistance and weatherability). In addition, the fabrication process will be scaled to accomodate prototype samples (12 inch x 12 inch, or larger) for customer evaluation. Commercial Applications and Other Benefits as described by the awardee: Self-cleaning surfaces have many applications and therefore several large market opportunities, such as architectural glass, automotive glass (where the self-cleaning feature can result in reduced vehicle weight by eliminating the need for cleaning fluids and improved driving safety), and cover glass of photovoltaic cells (increasing light transmission to the cells and thereby increasing the long-term efficiency of solar panels). It is estimated that self-cleaning surfaces could yield energy savings of over $100 million a year by removing the need for washing, scrubbing, and chemically polishing windows, ceramics, and other surfaces.