Powering the future: application of cellulose-based materials for supercapacitors
In recent years, significant research has aimed at developing environmentally friendly supercapacitors by introducing biopolymeric materials, such as polysaccharides or proteins. In addition to the sustainability and recyclability of such novel energy storage devices, these polymers also provide flexibility, lightweight nature and stable cycling performance, which are of tremendous importance for applications related to wearable electronics. Among the different sustainable natural polymers, cellulose deserves special consideration since it is the most abundant and is extensively recycled. Consequently, research on electrically active cellulose-based supercapacitors has noticeably increased since 2012, which makes this review on the field timely. Specifically, recent advances in preparing high performance cellulose supercapacitors are summarized. Moreover, the key roles of cellulose in improving the specific capacitance and cycling stability of cellulose-based devices are compiled to offer important fundamental guidelines for designing the next generation of all-cellulose energy storage devices that are to come. Finally, challenges and perspectives in this exciting area of study are also discussed.