Dual Band 1 Dual-band electrochromic 1 Electrochromic devices 1 Electrochromic materials Electrochromics 1 Electrochromism 1 Energy efficiency 1 Infrared devices 1 Light modulation 1 Nanoparticles 1 Near infrared light 1 Optical signal processing 1 Oxygen deficient 1 Oxygen-deficient WO3-x 1 Smart window 1 Smart windows 1 Sol- gel methods 1 Sol-gel method 1 Sol-gel process 1 Sol-gels 1 Solvothermal synthesis 1 Synthesis (chemical) 1 Temperature 1 Tungsten compounds 1