Improved pseudocapacitive performance of well-defined WO3−x nanoplates

We demonstrate the well-defined tungsten suboxide nanoplates for pseudocapacitors via a low-temperature reduction reaction under hydrogen gas atmosphere. The as-prepared WO3−x reduced at 500 °C using WO3 nanoplates (500-WO3−x) shows a pure monoclinic structure and single crystalline nanoplates. The 500-WO3−x exhibits much improved pseudocapacitive performance due to W5+ and W4+ oxidation states obtained by a reduction process and improved electrical conductivity.