Excellent Electrochromic Properties of Ti⁴⁺-Induced Nanowires V₂O₅ Films

Ti⁴⁺-doped V₂O₅ films with nanowires on top and a dense, long nanorod layer on the bottom were successfully fabricated using the spin-coating route. During the electrochromic cycling, charge transfer resistance (R) decreases while ion-diffusion ability (K) rapidly drops in the first ten cycles and then levels off. Low R and morphology of nanowires collaboratively improved the electrochromic behavior of Ti⁴⁺-doped V₂O₅ films by enhancing the charge transfer speed and minimizing polarization and dissolution. The obtained Ti⁴⁺-doped V₂O₅ film shows better electrochromic properties than the undoped V₂O₅ film, with a coloration efficiency (CE) of 34.15 cm²/C, coloration time of 9.00 s, and cyclic retention of 82.6% at cycle 100. In contrast, the corresponding values for the undoped V₂O₅ film were 23.57 cm²/C, 13.16 s, and 43.6%.