Controlling Porosity in Lignin-Derived Nanoporous Carbon for Supercapacitor Applications

Low‐cost renewable lignin has been used as a precursor to produce porous carbons. However, to date, it has not been easy to obtain high surface area porous carbon without activation processes or templating agents. Here, we demonstrate that low molecular weight lignin yields highly porous carbon with more graphitization through direct carbonization without additional activation processes or templating agents. We found that molecular weight and oxygen consumption during carbonization are critical factors to obtain high surface area, graphitized porous carbons. This highly porous carbon from low‐cost renewable lignin sources is a good candidate for supercapacitor electrode materials. Low‐cost renewable lignin is used as a precursor to produce high surface area, graphitized porous carbons for supercapacitor applications. Molecular weight and oxygen consumption during carbonization are critical factors in controlling the structure and, consequently, capacitor performance. The carbonized residues exhibit good electrochemical performance in terms of high specific capacitance, high energy density and power, and good capacity retention.