One‑Pot Rational Deposition of Coaxial Double‑Layer MnO_(2)/Ni(OH)_(2) Nanosheets on Carbon Nanofibers for High‑Performance Supercapacitors

Constructing“nanoglue”between inorganic electroactive species and conductive carbon scaffolds is an effective strategy to improve their compatibility and binding interaction,holding a great promise for fabricating high-performance hybrid electrodes for supercapacitors.However,multistep reactions are usually required to obtain these multicomponent systems,thus giving rise to the complicated and time-consuming issues.Herein,we for the first time,demonstrate a green one-pot method to anchor coaxial double-layer MnO_(2)/Ni(OH)_(2)nanosheets on electrospun carbon nanofibers(CNFs)(denoted as MNC),where the intermediate MnO_(2)layer serves as the“nanoglue”to couple the vertically aligned Ni(OH)_(2)nanosheets and conductive CNFs.Benefiting from the unique chemical composition and hierarchical architecture,the resultant electrode delivers outstanding electrochemical performance,including an excellent specific capacitance(1133.3 F g^(-1)at 1 A g^(-1))and an ultrahigh rate capability(844.4 F g^(-1)at 20 A g^(-1)).Moreover,the asymmetric supercapacitor assembled by using the MNC as positive electrode and the CNF as negative electrode can achieve an optimal energy density of 35.1 Wh kg^(-1)and a maximum power density of 8000 W kg^(-1).The one-pot strategy that stabilizes electroactive metal hydroxides on conductive carbons using a MnO_(2)“nanoglue”to design advanced hybrid electrodes is expected to be broadly applicable not only to the supercapacitor technology but also to other electrochemical applications.