Cobalt Hydroxide Nanosheets Grown on Carbon Nanotubes Anchored in Wood Carbon Scaffolding for High-Performance Hybrid Supercapacitors

Abstract

A novel green and sustainable self-supporting electrode for an excellent performance hybrid supercapacitor (HSC) based on hybridizing Co­(OH)2 nanosheets with carbon nanotube (CNT) arrays in wood carbon scaffolding made of Chinese fir waste is designed. The composite electrode has an area specific capacity as high as 4.17 mA h cm–2 due to the synergy of the wood carbon scaffolds, CNTs, and Co­(OH)2 nanosheets. The HSC constructed with the composite electrode and the CNT/carbonized wood electrode obtains a specific capacitance of 2.88 F cm–2, and after 11,000 cycles, the capacity retention rate of the HSC is still 97.8%, and its maximum energy and power density are 0.78 mW h cm–2 and 34.40 mW cm–2, respectively. The in situ growth of CNTs in carbonized wood can avoid aggregation and provide fast electron-transfer paths, and CNTs are wrapped by Co­(OH)2 nanosheets by electrochemical deposition to obtain excellent electrochemical energy storage performance. This novel family of wood-derived materials represents a general and abundant candidate toward real-world energy storage applications.

Semi-Embedding Zn-Co3O4 Derived from Hybrid ZIFs into Wood-Derived Carbon for High-Performance Supercapacitors

“…The area-specific capacitances of CW-230, Zn@CW-230, and Co 3 O 4 @CW-230 are 2.32, 6.03, and 4.46 F cm −2 at 10 mA cm −2 , respectively ( Figure S6 ). This is due to the high conductivity of wood-derived carbon substrate and easy electrolyte penetration, and better utilization of Co 3 O 4 electroactive surface in the redox reaction [ 44 , 45 ], which is consistent with the results inferred from the previous characterization. In Figure 4 d, the electrochemical performances were further explored by EIS, and the Nyquist plots were fitted with an equivalent circuit diagram ( Figure S8 ).…”

Biomass-derived porous carbon materials: synthesis, designing, and applications for supercapacitors

“…17a). 186 Carbon nanotubes were coated with Co(OH) 2 to form a conductive network, and then dispersed in Co(OH) 2 nanosheets. The Co(OH) 2 nanosheets were evenly arranged and connected to each other to form a staggered network structure, which was conducive to the interaction between electrode materials and electrolyte, accelerating ion transport and the electrochemical reaction.…”

Free-Standing Co(OH)2/Prussian Blue Analogue Nanostructured Electrodes for Flexible Na-Ion Supercapacitors with an Ultrawide Potential Window

“…6 Layered metal hydroxides (LMHs) with high theoretical specific capacitance, abundant resources, easy-to-synthesize, and nontoxic characteristics are regarded as one competitive candidate for FSCs. 7,8 However, the low conductivity and structural collapse during charging/discharging severely limit their charge transfer and electrochemical performances. 9 Many efforts have been devoted to overcoming the above drawbacks.…”