The synthesis of hierarchical ZnCo₂O₄@MnO₂core–shell nanosheet arrays on Ni foam for high-performance all-solid-state asymmetric supercapacitors

Abstract

ZnCo2O4@MnO2 core–shell nanosheet arrays synthesized via a two-step hydrothermal method exhibited an extraordinary electrochemical performance.

Metal–Organic Framework Templated 3D Hierarchical ZnCo2O4@Ni(OH)2 Core–Shell Nanosheet Arrays for High‐Performance Supercapacitors

“…Ragone plots are shown in Figure h, in which the energy and power densities of the as‐prepared ZnCo 2 O 4 @Ni(OH) 2 //AC ASC device are compared with those of devices previously reported in the literature. The ASC device can deliver the maximum energy density of 40.0 Wh kg −1 at a power density of 802.7 W kg −1 , and the maximum power density of 8.02 kW kg −1 at an energy density of 17.6 Wh kg −1 , which outperforms many ASCs based on core–shell electrodes reported previously, such as NiCo 2 S 4 @Co(OH) 2 //AC (35.89 Wh kg −1 at 0.4 kW kg −1 ), ZnCo 2 O 4 @MnO 2 //AC (29.41 Wh kg −1 at 0.63 kW kg −1 ), Co 3 O 4 @Co(OH) 2 //AC (25.6 Wh kg −1 at 0.93 kW kg −1 ), ZnCo 2 O 4 @MnCo 2 O 4 //AC (19.12 Wh kg −1 at 0.75 kW kg −1 ), Cu@CuO//AC(35.43 Wh kg −1 at 0.52 kW kg −1 ) and so on. Moreover, two connected ZnCo 2 O 4 @Ni(OH) 2 //AC ASCs in series afforded 3.2 V of working potential, and kindled a LED light bulb for 2.1 min (Figure b).…”

Designing an Advanced Supercapattery Based on CuCo2S4@Ni−Mo−S Nanosheet Arrays

“…[1][2][3][4][5][6] SCs are considered as one of the intriguing candidates for next-generation ESDs owing to their obvious merits like considerable power density, amazing robustness, and rapid charging-discharging rate, but the relatively insignificant specific energy restricts their usages. [7][8][9][10][11] Conversely, batteries have great specific energy, but low power density. [12,13] An ESD based on a capacitive electrode (e. g. AC) and battery-type electrode (e. g. metal oxide or metal sulfide) named supercapattery, proposes a promising approach to design system with merits of SCs and batteries.…”

“…SCs are considered as one of the intriguing candidates for next‐generation ESDs owing to their obvious merits like considerable power density, amazing robustness, and rapid charging‐discharging rate, but the relatively insignificant specific energy restricts their usages . Conversely, batteries have great specific energy, but low power density .…”

MnO2‐Based Materials for Environmental Applications

“…Many heterojunctions formed by AB 2 O 4 spinel and MnO 2 have also been reported in recent years, including ZnCo 2 O 4 /MnO 2 , [ 232–236 ] ZnFe 2 O 4 /MnO 2 , [ 237 ] CoFe 2 O 4 /MnO 2 , [ 238 ] MnFe 2 O 4 /MnO 2 , [ 239 ] MnCo 2 O 4 /MnO 2 , [ 240 ] NiCo 2 O 4 /MnO 2 , [ 241,242 ] and CuBi 2 O 4 /MnO 2 . [ 243,244 ] Zhang et al.…”