Carbon-encapsulated tungsten oxide nanowires as a stable and high-rate anode material for flexible asymmetric supercapacitors

Herein, we report an effective carbon encapsulation strategy to boost the capacitive performance of WO3−x nanowires as a high-energy and stable anode material for flexible asymmetric supercapacitors (ASCs). The carbon-encapsulated WO3−x nanowires exhibited a remarkable areal capacitance of 786.8 mF cm−2 and excellent durability. Furthermore, an ASC device with high energy and power density was also fabricated from the as-prepared carbon encapsulated WO3−x nanowire anode.