Matching design of high-performance electrode materials with different energy-storage mechanism suitable for flexible hybrid supercapacitors

The realization of advanced hybrid supercapacitors needs the optimal match of different types of high-performance electrode materials. Porous biomass carbon with high specific surface area of 2217.8 m2 g−1 and large specific capacity of 112.5 mAh g−1 (337 F g−1) is prepared from cornstalk. Battery-type Ni3Se2 nanoarray materials with ultra-long nanowire array structure and the specific capacity of 132.4 mAh g−1 are synthesized via a facile solvothermal method. Due to the structure and performance advantages of porous biomass carbon and Ni3Se2 nanoarrays, flexible hybrid supercapacitors are assembled by matching-design of electrode materials with different energy-storage mechanism. This full-cell flexible hybrid device has a wide voltage window of 0–1.6 V, superior energy density of 38.8 Wh kg−1, excellent mechanical flexibility and low-temperature resistance. Therefore, the current work not only shows a feasible designing-method for flexible hybrid supercapacitors, but also provides a promising candidate for small, flexible, and smart electronic device.