Pinus nigra pine derived hierarchical carbon foam for high performance supercapacitors

Biomass comprises an attractive source of carbon materials for energy conversion and storage applications, because it provides a low cost and sustainable approach for the production of carbon-based electrode materials at large scale. Here, we demonstrate the preparation of a three-dimensional and hierarchical carbon foam (3DCF) from bio-renewable Pinus nigra pine, using a chemical degradation method followed by two simple carbonization steps in presence of argon gas. The as-prepared 3DCF in supercapacitor electrode shows high scan rate capability up to 10 V s−1, specific capacitance of 165 F g−1 at the specific current of 3.3 A g−1 in 6 M KOH electrolyte in three-electrode cell configuration, and retains 69.6% of its initial capacitance when the specific current increased to 13.3 A g−1. Furthermore, a 3DCF based symmetrical two-electrode cell has been constructed that shows a satisfactory specific energy of 6.6 Wh kg−1 at specific power of 2.3 kW kg−1, and maintains the specific energy of about 50% at high specific power of 7.3 kW kg−1 under an operating voltage of 1.4 V in 2 M LiClO4 aqueous electrolyte. These results reveal a sustainable and low-cost electrode fabrication at large quantity for fabricating high performance supercapacitors with both KOH and Li-ion based electrolytes.