Design of a Scalable Dendritic Copper@Ni²⁺, Zn²⁺ Cation-Substituted Cobalt Carbonate Hydroxide Electrode for Efficient Energy Storage

Abstract

Design and fabrication of novel electrode materials with excellent specific capacitance and cycle stability are urgent for advanced energy storage devices, and the combinability of multiple modification methods is still insufficient. Herein, Ni 2+ , Zn 2+ double-cation-substitution Co carbonate hydroxide (NiZnCo-CH) nanosheets arrays were established on 3D copper with controllable morphology (3DCu@NiZnCo-CH). The selfstanding scalable dendritic copper offers a large surface area and promotes fast electron transport. The 3DCu@NiZnCo-CH electrode shows a markedly improved electrochemical performance with a high specific capacity of ∼1008 C g −1 at 1 A g −1 (3.2, 2.83, and 1.26 times larger than Co-CH, ZnCo-CH, and NiCo-CH, respectively) and outstanding rate capability (828.8 C g −1 at 20 A g −1 ) due to its compositional and structural advantages. Density functional theory (DFT) calculation results illustrate that cation doping adjusts the adsorption process and optimizes the charge transfer kinetics. Moreover, an aqueous hybrid supercapacitor based on 3DCu@NiZnCo-CH and rGO demonstrates a high energy density of 42.29 Wh kg −1 at a power density of 376.37 W kg −1 , along with superior cycling performance (retained 86.7% of the initial specific capacitance after 10,000 cycles). Impressively, these optimized 3DCu@NiZnCo-CH//rGO devices with ionic liquid can be operated stably in a large potential range of 4 V with greatly enhanced energy density and power capability (110.12 Wh kg −1 at a power density of 71.69 W kg −1 ). These findings may shed some light on the rational design of transition-metal compounds with tunable architectures by multiple modification methods for efficient energy storage.

Hierarchical CuCo Carbonate Hydroxide Nanowires@FeCo‐Layered Double Hydroxide Hexagonal Nanosheets of Penetrating Architecture for High‐Performance Asymmetric Supercapacitor

“…Even when the power density expands tenfold to 7500 W kg À 1 , the energy density still remains at 29.0 Wh kg À 1 . Notably, the energy storage performance of the as-fabricated CuCo-CH@FeCo-LDH//NSrGO ASC exceeds that of most similar devices in previous reports, such as Co-CH/ Ni-CH//AC (39.2 Wh kg À 1 at 800 W kg À 1 ), [30] Co-Co LDH/C/Ni-(OH) 2 //AC (42.9 Wh kg À 1 at 375 W kg À 1 ), [50] NiZnCo-CH//rGO (42.3 Wh kg À 1 at 376 W kg À 1 ), [51] and Co-CH@NiMnCo-CH//AC (20.3 Wh kg À 1 at 748 W kg À 1 ). [52] Lastly, a yellow LED was lighted by two ASC devices in series (Figures 6f and S14).…”

Heterostructured Co-NTC@Co3S4 as an anode material for asymmetric pseudocapacitors

“…6(a) shows that the coating area of Co-NTC@Co 3 S 4 increases, which can indicate that the sample has excellent rate performance. The possible reaction of the electrode can be expressed as below: 34,39 Co-NTC@Co 3 S 4 reveals a quite high specific capacitance value of 3115.1 F g −1 , and by contrast, the specific capacitance values of ZIF-67, ZIF-67-S and ZIF-67@Co-NTC are just 63.9 F g −1 , 1395.8 F g −1 and 494.9 F g −1 , respectively.…”

“…6(a) shows that the coating area of Co-NTC@Co 3 S 4 increases, which can indicate that the sample has excellent rate performance. The possible reaction of the electrode can be expressed as below: 34,39 Co 3 S 4 + OH − ↔ Co 3 S 4 OH + e − Co 3 S 4 OH + OH − ↔ Co 3 S 4 O + H 2 O + e − …”

Self-templated flower-like NiCoZn-carbonate hydroxide hollow nanospheres for asymmetric supercapacitors with high performance

“…To further improve electrical conductivity, elemental substitution is a valid method. 21,22 The addition of appropriate amounts of Zn can accelerate the electron/ion transfer and enhance the electrochemical stability and activity of NiCo-CH. 23,24 In this work, novel flower-like NiCoZn-carbonate hydroxide (NiCoZn-CH) hollow nanospheres are successfully synthesized by two-step solvothermal synthesis.…”

“…To further improve electrical conductivity, elemental substitution is a valid method. 21,22 The addition of appropriate amounts of Zn can accelerate the electron/ion transfer and enhance the electrochemical stability and activity of NiCo-CH. 23,24…”