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Highlights • 3D porous CF is prepared using sponge as template and C 5 H 6 O 2 as carbon source. • PANI nanowires are deposited at the CF by a facile electrodeposition method. • CF-PANI exhibits good electrochemical performances. • The asymmetric supercapacitor assembled with CF-PANI and CF shows high energy and power densities. Abstract In this paper, three-dimensional (3D) porous carbon framework (CF) is prepared using commercial sponge as template and furfuryl alcohol (C 5 H 6 O 2) as carbon source, through polymerizing and solidifying by oxalic acid (H 2 C 2 O 4) followed by a carbonizing process at high temperature. Then, one-demensional (1D) polyaniline (PANI) nanowires are deposited on the CF substrate by a simple one-step electrodeposition method to obtain CF-PANI energy storage electrode. The CF-PANI maintains initial 3D porous structure as CF substrate with PANI layer, benefiting for the diffusion of electrolyte and the contact between active material and electrolyte. Besides, the carbon skeleton is surrounded by the PANI nanowires, which provide more transfer channels for electrons during the charge/discharge process. The loading mass of PANI on CF is as high as 21.3 mg cm−3, and the gravimetric and volumetric capacitances reach 866 F g−1 and 18.5 F cm−3, respectively, at the scan rate of 2 mV s−1. Moreover, the asymmetric supercapacitor based on CF-PANI as anode electrode and CF as cathode electrode exhibits a high energy density of 44 W h kg−1 at the power density of 800 W kg−1, indicating its promising applications as the electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

Graphical abstract The super-ionic conductivity nanowire Cu 2 Se/Ni-foam electrode processes excellent cycling performance and the electrode is firstly assembled to asymmetric supercapacitor achieving high energy and power density. Abstract Transition metal selenide has stimulated much research interest in energy storage and conversion, due to its excellent electrical conductivity. β-Cu 2 Se with special crystal structure is considered as super-ionic conductor, of which the diffusion coefficient is as large as a liquid. The fast ions and electrons conductor β-Cu 2 Se with uniformly dense nanowire crossing with each other directly on nickel foam is prepared via simple one-step solvothermal grow method for 4 h, avoiding conductive agent and binder. The feature much benefitting for electrons and ions transfer enable the β-Cu 2 Se-4h electrode delivers specific capacity as high as 182.4 mA h g−1 at current density of 2 mA cm−2, which is still 105.6 mA h g−1 even at high current density of 50 mA cm−2, and excellent cycling stability of 85% after repetitively charge-discharge 10,000 times. The fabricated asymmetric supercapacitor (β-Cu 2 Se-4h//AC) achieves maximum energy and power density is 48 Wh kg−1 and 5500 W kg−1. [ABSTRACT FROM AUTHOR]

Novel Au@Ni nanoarrays electrode is facilely obtained by firstly template-assisted electro-deposition of Ni nanowire arrays (NAs), followed by galvanostatic deposition of Au catalysts onto the Ni NAs without any conductive agents and binders. The Au@Ni NAs electrode shows a rough surface and fringe with the diameter of ∼90 nm, which assures a high utilization of Au catalysts and provides a large specific surface area. The elemental distribution of Ni mainly exists in the inner layer of a single Au@Ni nanowire with the diameter ∼56 nm, while the elemental distribution of Au catalysts merely appears in the outer layer to form the unique core-shell nanowire structure. The Au@Ni NAs electrode reveals excellent electrochemical property and desirable stability for catalyzing NaBH 4 electro-oxidation in basic solutions. The Au@Ni NAs electrode in the 2.00 M NaOH and 0.24 M NaBH 4 solution demonstrates an oxidation current density of 2.35 A mg −1 at −0.5 V (vs. Ag/AgCl), which is much higher than that of the noble metal catalysts previously reported, indicating that this material may be hopefully used as anodic catalysts for applying in fuel cells. [ABSTRACT FROM AUTHOR]