Hierarchical cellulose-derived carbon nanocomposites for electrostatic energy storage

The prob­lem of energy stor­age and its con­tinu­ous deliv­ery on demand needs new effect­ive solu­tions. Super­ca­pa­cit­ors are viewed as essen­tial devices for solv­ing this prob­lem since they can quickly provide high power basic­ally count­less num­ber of times. The per­form­ance of super­ca­pa­cit­ors is mostly depend­ent on the prop­er­ties of elec­trode mater­i­als used for elec­tro­stat­ic charge accu­mu­la­tion, i.e. energy stor­age. This study presents new sus­tain­able cel­lu­lose-derived mater­i­als that can be used as elec­trodes for super­ca­pa­cit­ors. Nan­ofibrous car­bon nan­ofiber (CNF) mats were covered with vapor-grown car­bon nan­otubes (CNTs) in order to get com­pos­ite CNF/​CNT elec­trode mater­i­al. The res­ult­ing com­pos­ite mater­i­al had sig­ni­fic­antly high­er sur­face area and was much more con­duct­ive than pure CNF mater­i­al. The per­form­ance of the CNF/​CNT elec­trodes was eval­u­ated by vari­ous ana­lys­is meth­ods such as cyc­lic voltam­metry, gal­vano­stat­ic charge-dis­charge, elec­tro­chem­ic­al imped­ance spec­tro­scopy and cyc­lic sta­bil­ity. The res­ults showed that the cel­lu­lose-derived com­pos­ite elec­trodes have fairly high val­ues of spe­cif­ic capa­cit­ance and power dens­ity and can retain excel­lent per­form­ance over at least 2,000 cycles. There­fore it can be stated that sus­tain­able cel­lu­lose-derived CNF/​CNT com­pos­ites are pro­spect­ive mater­i­als for super­ca­pa­cit­or electrodes.