Carbon Nanotubes/​Nanofibers Composites from Cellulose as Electrodes for Sustainable Energy Devices

Car­bon nan­ofibers (CNF) with well inter­con­nec­ted pores, mech­an­ic­al and elec­tro­chem­ic­al sta­bil­ity are pro­spect­ive elec­trode mater­i­als for vari­ous energy devices.They sus­tain a sub­stan­tial uptake of elec­tro­lyte solu­tion and enable high ion con­duct­iv­ity; their freest­and­ing nature allows using them without poly­mer­ic binder.CNF are par­tic­u­larly­suit­able for super­ca­pa­cit­ors with high power dens­ity and long life-cycle per­form­ance that can be applied in sus­tain­able elec­tricve­hicles. As a demand on car­bon nano­struc­tures con­tin­ues to grow, renew­able resources should be accoun­ted as an altern­at­ive to the cur­rently most used CNF pre­curs­ors: coal tar pitch and syn­thet­ic poly­mers. The biopoly­mer cel­lu­lose is a vast source for the syn­thes­is of CNF. How­ever, the main draw­backs of the CNF mater­i­al are its rel­at­ively low spe­cif­ic sur­face area and elec­tric­al con­duct­iv­ity, which leads to low val­ues of spe­cif­ic capa­cit­ance. In this work, cel­lu­lose-based CNF with high mech­an­ic­al strength and elec­tro­chem­ic­al sta­bil­ity were nitro­gen-doped and func­tion­al­ized with car­bon nan­otubes (CNT) via two dif­fer­ent meth­ods in order to get enhanced elec­trode mater­i­als for supercapacitors.