Hierarchical core–shell heterostructure of porous carbon nanofiber@ZnCo₂O₄nanoneedle arrays: advanced binder-free electrodes for all-solid-state supercapacitors

Abstract

Hierarchical ZnCo2O4 nanoneedle arrays are vertically grown on porous carbon nanofibers (PCFs) to form a core–shell heterostructure through a facile hydrothermal method followed by thermal treatment.

Hierarchical 3D Cobalt‐Doped Fe3O4 Nanospheres@NG Hybrid as an Advanced Anode Material for High‐Performance Asymmetric Supercapacitors

“…Based on the GCD curves at various current densities from 1 to 20 A g −1 , the calculated specific capacitance of the ASC device was shown in Figure d. The CoMnO 3 @NG//Co−Fe 3 O 4 NS@NG ASC achieved high specific capacitance of 198 F g −1 at a current density of 1 A g −1 , which is higher than that recently reported for iron oxide‐based ASCs . The ASC device accomplished a prominent rate capability with 75% of capacitance retention at a high current density of 20 A g −1 .…”

Enhancing Energy Storage via TEA‐Dependent Controlled Syntheses: Two Series of Polyoxometalate‐Based Inorganic‐Organic Hybrids and their Supercapacitor Properties

“…The two redox couples (I–I’) and (II–II’) can be attributed to two steps of single‐electron redox processes of tungstate, namely, [H 2 W VI 12 O 40 ] 6− +e − =[H 2 W VI 11 W V O 40 ] 7− and [H 2 W VI 11 W V O 40 ] 7− +e − =[H 2 W VI 10 W V 2 O 40 ] 8− . These slight shifts of redox peaks of the SiW ‐ 2 and W ‐ 1 can be ascribed to the internal resistance and polarization effect of the electrodes . Additionally, the current response of all of the redox peaks increased linearly with changing scan rates from 5–100 mV s −1 , as shown in the inset plots of Figure .…”

PVP assisted morphology-controlled synthesis of hierarchical mesoporous ZnCo 2 O 4 nanoparticles for high-performance pseudocapacitor

“…Cyclic voltammetry (CV) tests were done in the potential window of 0.2 -0.7 V at different scan rates (2, 5, 10, 20, 50 and 100 mV s -1 ). The specific capacitance of the fabricated electrode can be calculated based on the cyclic voltammograms according to the following equation [27] …”

“…Additionally, Niu et. al[27] synthesized a hierarchical core-shell heterostructure of porous carbon nanofiber@ZnCo 2 O 4 nanoneedle arrays through electrospinning and hydrothermal process, got the highest specific capacitance value in the group at current density of 5 A g -1 . However, comparing the calculated specific capacitance values based on the cyclic voltammograms at scan rate of 2 mV s -1 , our materials showed the best results.…”