Nanocomposite Counter Electrode Materials for Electrochromic Windows

Nickel-oxide-based nanocomposite films were deposited using radio-frequency magnetron sputtering from ceramic targets composed of lithium, nickel, and tungsten oxides. The resulting films are partially prelithiated and exhibit a slight spectral shift relative to tungsten-free films when colored. Electron microscopy and X-ray diffraction show that the films are composed of nanocrystallites with NiO structure. The films show promise as electrochromic counter electrode layers that are durable, efficient, and fabricated using a scalable, economical process.