Construction of CoO/Co‐Cu‐S Hierarchical Tubular Heterostructures for Hybrid Supercapacitors

Abstract

Hierarchical hollow structures for electrode materials of supercapacitors could enlarge the surface area, accelerate the transport of ions and electrons, and accommodate volume expansion during cycling. Besides, construction of heterostructures would enhance the internal electric fields to regulate the electronic structures. All these features of hierarchical hollow heterostructures are beneficial for promoting the electrochemical properties and stability of electrode materials for high‐performance supercapacitors. Herein, CoO/Co‐Cu‐S hierarchical tubular heterostructures (HTHSs) composed of nanoneedles are prepared by an efficient multi‐step approach. The optimized sample exhibits a high specific capacity of 320 mAh g−1 (2300 F g−1) at 2.0 A g−1 and outstanding cycling stability with 96.5 % of the initial capacity retained after 5000 cycles at 10 A g−1. Moreover, an all‐solid‐state hybrid supercapacitor (HSC) constructed with the CoO/Co‐Cu‐S and actived carbon shows a stable and high energy density of 90.7 Wh kg−1 at a power density of 800 W kg−1.

Zephyranthes-like Co2NiSe4 arrays grown on 3D porous carbon frame-work as electrodes for advanced supercapacitors and sodium-ion batteries

“…5(a). According to relevant literature, the relationship between scan rate (v) and peak current (i) can be summarized as follows [38]…”

Precise regulation of pyrrole‐type single‐atom Mn‐N4 sites for superior pH‐universal oxygen reduction

“…[7][8][9] Therefore, increasingly more studies have focused on the development of cost-effective nonnoble metal catalysts for the replacement of the platinum-based catalysts. [10][11][12] In recent years, transition-metal (TM) single-atom catalysts (SACs) have been found to be effective in ORR, including Cr-N 4 , 13 Fe-N 4 , 14 Fe-N 5 , 15 Co-N 4 , 16 Ni-N 4 , 17 Cu-N 3 , 18 and Zn-N 4 19 sites. These TM SACs have been regarded as the most promising alternatives to commercial Pt/C catalysts.…”

Rational Design and Engineering of One‐Dimensional Hollow Nanostructures for Efficient Electrochemical Energy Storage

“…reported the synthesis of CoO/Co-Cu-S hierarchical tubular heterostructures through at emplating strategy (Figure 8d). [163] TheF ESEM images show the gradual evolution of the morphologies (Figure 8e-h). Impressively,t he hybrid supercapacitor device based on this CoO/Co-Cu-S cathode and an activated carbon anode manifested ah igh rate capability,w ith 71 %o fthec apacity maintained when the current density was elevated from 1.0 Ag À1 to 20 Ag À1 (Figure 8i); furthermore,acapacity retention of 95 %o ver 5000 cycles was achieved (Figure 8j).…”