• A flexible dual-band electrochromic device achieves high optical modulation (73.1% at 633 nm, 85.3% at 1200 nm) and long cycle life (3.3% capacity loss after 10,000 cycles).
• The device independently modulates visible and near-infrared light through three distinct modes, offering superior energy-saving performance compared to commercial low-emissivity glass in most global climates.
• Integrating energy storage, the device exhibits high capacitance and an energy recycling efficiency of 51.4%, enabling local reuse of energy consumed during coloration.
• The nanowire structure and oxygen vacancies of oxygen-deficient tungsten oxide provide excellent flexibility and durability, making the device suitable for practical smart window applications.