Electrochromic—or “smart”—windows improve energy efficiency, provide privacy, and optimize lighting conditions. Critical factors in the production of smart glass include material costs, installation costs, durability, and the optimization of function. This virus-based method for the production of electrochromic materials generates uniquely functional electrochromic nanowires. The nanowires feature enhanced charge extraction (i.e., better colorization efficiency), enhanced color retention (10 days versus 600 seconds with traditional TiO2 devices), and an exceptionally rapid response rate (1 millisecond). Additionally, the virus-based fabrication method is simple, inexpensive, rapid, and can be performed in solution under ambient conditions.