Bistable Visible‐Near‐Infrared Dual‐Band Electrochromic Materials With Dynamical Light/Heat Modulation Performance Based on the Synergetic Effect Between TiO 2 /WO 3 Composite Nanorod Arrays and Aqueous Al 3+

ABSTRACT The dual‐band electrochromic materials, capable of independently regulating visible (VIS) and near‐infrared (NIR) transmittance, have emerged as an attractive approach to reduce building energy consumption. However, the existing materials still have some inevitable problems, including weak ability of selectively regulating VIS/NIR transmittance and poor cycle stability. Herein, the dynamic modulation of dual band was achieved through the synergetic effect between TiO 2 /WO 3 composite nanorod arrays (TWNRAs) and aqueous Al 3+ . Benefiting from the high specific surface area and large cavity structure, the prepared TWNRAs achieved three functional electrochromic modes in dual‐band: “bright”, “cool,” and “dark” with high optical modulations (77.0%∼700 nm, 85.4%∼1000 nm). In addition, the TWNRAs also exhibited fast coloring/bleaching response (17 s/18s∼700 nm, 8 s/75 s∼1000 nm), high coloration efficiency (73.04 cm 2 ·C −1 ∼700 nm; 166.59 cm 2 ·C −1 ∼1000 nm), and good bistable stability (transmittance remained 89%/79% at 700 nm/1000 nm after 2000 cycles, capacity remained 88.6%). In addition, by quantitatively analyzing the electrochemical behavior of Al 3+ during the charging process, the key role was confirmed to be the near‐surface pseudo capacitance, which strengthened the electrochromic stability and response. The mechanism of modulating the VIS and NIR lights was mainly attributed to the intraband/interband transition and localized surface plasmon resonance (LSPR), respectively.