Lignin-derived electrode materials for supercapacitor applications: progress and perspectives

Lignin is one of the most abundant natural polymers and is affordable, has high carbon content and abundant active functional groups. At present, lignin-derived carbon is considered an ideal, promising electrode material for supercapacitor applications and this route is showing a vigorous development trend. In this review, we summarize the progress of lignin-derived materials for supercapacitor applications. Firstly, the concept, classification strategy and basic chemistry of lignin are introduced in brief. Then, the up-to-date developments of the synthesis strategies of carbon electrodes from lignin for supercapacitors are reviewed in detail. Finally, the work is summarized and the major challenges of the lignin-based supercapacitors are discussed. This review is presented to guide the synthesis of lignin-based electrodes for supercapacitors and facilitate their widespread application. Lignin is one of the most abundant natural polymers and is affordable, has high carbon content and abundant active functional groups. It has been utilized as electrode materials in electrical double-layer supercapacitors and pseudo-supercapacitors.