MCA: Scalable Nanomanufacturing of Earth-Abundant Electrochromics

Cornell University, Ithaca NY

Investigators

Abstract

By actively managing solar radiation and visible light coming through windows, peak electricity demand in the U.S. could be reduced. Electrochromic, or “smart,” windows control light transmission by reversibly changing their opacity, stimulated by electrochemistry. Significant challenges hinder their implementation because smart windows made from the most popular metal oxide materials are prohibitively costly to manufacture. This Mid-Career Advancement award supports fundamental research to provide needed knowledge for the development of an earth-abundant materials platform for electrochromics that is amenable to scalable nanomanufacturing. The target materials are ternary copper sulfide semiconductors. Copper sulfide nanoparticles are more easily synthesized than metal oxides, and are made from low-cost, highly available elements. This award will advance discovery and understanding through the investigation of alternative nanomaterials with metal-like properties that could outperform traditional materials in optical applications. This research involves several disciplines including manufacturing, electrochemistry, chemical synthesis, and materials science. The multi-disciplinary approach will help broaden participation of underrepresented groups in research and positively impact engineering education. The outreach programs will invigorate public excitement about electrochromic windows. Nanoparticles of ternary copper sulfides have the ability to change their optical properties through electrochemical charging and discharging. This electrochromic effect can be enhanced by parameters such as size and composition. The team will investigate the working hypothesis that size, composition, and chemistry modifications to a metal-deficient copper sulfide phase will enable enhanced sensitivity to electrochemical modulation. The team will use “solventless” conditions (low ratio of ligand to cation) to control the nucleation and growth of the nanoparticles and enable scalability through a one-pot method. Electrodes will be assembled through electrophoretic deposition to establish a path toward scalable device integration. In addition, this Mid-Career Advancement award will provide protected time and resources for the PI to develop a collaboration with and learn from a Spanish expert in the field of nanoplasmonics. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.