Layer-stacked graphite-like porous carbon for flexible all-solid-state supercapacitor

Layer-stacked graphite-like porous carbon (LGPC) piled by uniform carbon sheets (100 ± 20 nm) with both improved graphitization degree and high specific surface area was synthesized by introducing catalytic activation strategy to coal tar pitch with easy polycondensation. Formation mechanism of LGPC was also revealed by summarizing exhausted gases analysis, Fe species transformation and morphologies varying during the whole catalytic graphitization process. The LGPC electrode exhibited higher specific capacitance (337.0F/g at 0.5 A/g) and faster rate capability (85.6% from 0.5 to 20 A/g) in three-electrode system. All-solid-state supercapacitor fabricated with double equal LGPC electrodes and PVA/KOH membrance displayed ideal capacitance characteristics and flexibility. Three series of the flexible cell could drive LED lights of different color (1.8–2.4 V) for more than 5 min. Moreover, this work provided a facile and novel route for effective utilization of coal-based heavy products and development of graphitized porous carbon.