Synthesis and Electrochemical Properties of Lignin-Derived High Surface Area Carbons

Activated carbons play an essential role in developing new electrodes for renewable energy devices due to their electrochemical and physical properties. They have been the subject of much research due to their prominent surface areas, porosity, light weight, and excellent conductivity. The performance of electric double-layer capacitors (EDLCs) is highly related to the morphology of porous carbon electrodes, where high surface area and pore size distribution are proportional to capacitance to a significant extent. In this work, we designed and synthesized several activated carbons based on lignin for both supercapacitors and Li-S batteries. Our most favorable synthesized carbon material had a very high specific surface area (1832 m(2)center dot g(-1)) and excellent pore diameter (3.6 nm), delivering a specific capacitance of 131 F center dot g(-1) in our EDLC for the initial cycle. This translates to an energy density of the supercapacitor cell at 55.6 Wh center dot kg(-1). Using this material for Li-S cells, composited with a nickel-rich phosphide and sulfur, showed good retention of soluble lithium polysulfide intermediates by maintaining a specific capacity of 545 mA center dot h center dot g(-1) for more than 180 cycles at 0.2 C.