Preparation of lily based porous carbon loaded Ni Co double hydroxide nanosheets complementary composite, its application in all-solid-state asymmetric supercapacitors

The combination of electric double-layer and pseudo-capacitive materials can complement and coordinate with each other, so that the electrode materials can obtain excellent specific energy and specific capacitance in supercapacitors. In this work, nanocomposites from Lily-based Porous activated Carbon Material (LPCM) loaded sheet-like NiCo Layered Double Hydroxide (LDH) have been prepared via the hydrothermal method in presence of hydrazine hydrate. Interestingly, the LPCM@NiCo-LDH-N2H4 electrode exhibits a high three-electrode specific capacitance of 705C g−1 at 1 A g−1 (577C g−1 at 30 A g−1), which is three times higher than the LPCM electrode. Furthermore, the assembled LPCM@NiCo-LDH-N2H4//LPCM asymmetric supercapacitor device displays an incredible specific energy (53.3 Wh kg−1) at 800 W kg−1 of specific power with virtually no capacitance loss after 10,000 cycles, outperforming many supercapacitor devices. Connecting two asymmetric devices can illumine a colored snowball and a small red LED for exceeding 13 min. The electrode materials with high specific energy and specific power obtained by the strategy have promoted the development of composite electrode materials for supercapacitors.