High-power-energy proton supercapacitor based on interface-adapted durable polyaniline and hexagonal tungsten oxide.

Supercapacitors are high power energy storage devices, however, their application are remain limited by the low energy density. Developing high capacity electrode materials and constructing devices with high operating voltage are effective ways to solve this problem. Herein, performance of polyaniline (PANI) electrode materials is dramatically enhanced by engineering robust PANI/carbon interfaces, through assembling PANI nanorod array on rose petals derived carbon network (RPDCN). The structure of the PANI is optimized by adjusting the concentration of the aniline precursor. The unique structure enables the prepared PANI/RPDCN composite show a high capacitance of 636 F g-1 at 0.5 A g-1, based on the total weight of PANI and RPDCN substrate. The robust interface effectively prolonged the composite electrode stably cycled for over 2000 cycles at 2 A g-1 with a capacity retention of 89%. When coupled with a hexagonal tungsten oxide (h-WO3) anode, a high-power asymmetric proton supercapacitor with high energy densities (29.0 Wh kg-1/0.61 kW kg-1 and 21.4 Wh kg-1/19.51 kW kg-1) was assembled. This work provides an effective and eco-friendly route toward superior PANI electrodes and proposes a promising high-power energy storage system using proton as working ion.