Highly ordered nano-tunnel structure of hydrated tungsten oxide nanorods for superior flexible quasi-solid-state hybrid supercapacitor

Battery-type materials are favorable candidates for realizing great specific capacity for supercapacitor devices. However, their slow kinematics impedes the enhancement in the electrochemical performance. Here, we report the extraordinary power and energy density are mutually filled into the quasi-solid-state flexible hybrid super-capacitor through intercalated pseudocapacitance of tunnel associated single-crystalline orthorhombic hydrated WO3 nanorods anode (battery-like) and exfoliated reduced graphene oxide (rGO) cathode (capacitive behavior). This single-crystalline orthorhombic hydrated WO3 nanorods structure inhibits active material accumulation and preserves a 1D directional arrangement associated with well-ordered large size hexagonal tunnels of about 0.612 nm along the (020) plane. It presents a high approachable surface area and hierarchically porous nature, facilitating abundant diffusion and carriage of electrolyte ions. The WO3 nanorods electrode exhibits the maximum specific capacitance of 539 F g(-1) at a scan rate of 2 mV s(-1) attributed to proton-accommodation into the nanotunnels of crystal structure and their defects associated enhanced redox processes. A flexible quasi-solidstate hybrid supercapacitor (HC) of WO3 nanorods//rGO has demonstrated the exceptional energy density 43.7 Wh kg(-1) and outstanding power density of 8.0 kW kg(-1) with better cyclic stability and the impressive robust flexibility performance, presenting a great prospective in realistic applications.

Automated summary

The study demonstrates the achievement of extraordinary power and energy density through intercalated pseudocapacitance, utilizing a novel structure composed of orthorhombic hydrated WO3 nanorods and reduced graphene oxide. This structure exhibits high specific capacitance and outstanding performance, showing great prospects for significant advancements in practical applications.