Single‐Step Anodization for the Formation of WO3‐Doped TiO2 Nanotubes Toward Enhanced Electrochromic Performance

Abstract Herein, we report a single‐step anodization process for WO 3 ‐doped TiO 2 nanotubes in an aqueous electrolyte containing the tungsten precursor Na 2 WO 4 ⋅ 2H 2 O and fluoride ions. The single‐step anodization allows for homogeneous doping of WO 3 into the TiO 2 nanotube structures. The doping concentration depends on the concentration of the tungsten precursor in the electrolyte, demonstrating that the reported anodizing process is the most efficient approach for metal oxide doping in TiO 2 . Moreover, compared to bare TiO 2 , the WO 3 ‐doped TiO 2 nanotubes shows better proton intercalation, which leads to enhanced electrochromic performance.