Construction of nanowall-supported-nanorod nico ldh array electrode with high mass-loading on carbon cloth for high-performance asymmetric supercapacitors

• Published in: Electrochimica acta Vol. 362; p. 137081
• Main Authors: Yang, Tianyi, Ye, Jing, Chen, Shihuan, Liao, Shuqing, Chen, Huizhen, Yang, Luhuan, Xu, Xuetang, Wang, Fan
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2020; Elsevier BV
• Subjects: Adhesive strength; Areal capacitance; Arrays; Carbon; Cloth; Data integration; Electrical resistivity; Electrodes; Electron transfer; Flux density; High mass-loading; Intermetallic compounds; Nanorods; NiCo LDH; Substrates; Supercapacitor; Supercapacitors; Weight reduction; Supercapacitor; High mass-loading; Areal capacitance; NiCo LDH
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2020.137081

•Nanowall-supported-nanorod nico LDH arrays with open holey framework are obtained.•Electrode with high loading of 5.85 mg cm−2 shows the capacitance of 7.73 F cm−2.•All-solid-state asymmetric supercapacitor delivers 6.37 mWh cm−3 at 62.5 mW cm−2. Carbon cloth is regarded as a promising substrate for supercapacitors due to its good electrical conductivity, light weight and flexibility. However, its relatively hydrophobic property prevents the large-scale growth of active substances, restricting the potential practical applications. In this paper, by using NiCo LDH nanowall array as a hydrophilic substrate, a high mass-loading nanowall-supported-nanorod NiCo LDH arrays are formed via an alternate solvo/hydrothermal synthesis and subsequently alkali conversion process. The strong substrate adhesion of NiCo LDH nanoarrays ensures efficient electron transfer of the electrode. Moreover, the as-achieved open holey framework, integrated by free-standing nanorods and porous nanowalls, provides a hierarchical nanostructure for realizing the enhanced capacitive performance. Consequently, nanowall-supported-nanorod NiCo LDH electrode achieves a high capacitance of 7.73 F cm−2 at a current density of 5 mA cm−2 with excellent rate performance. When assembled into an all-solid-state hybrid supercapacitor, it delivers a maximum working voltage of 1.8 V, and an energy density of 0.46 mWh cm−2 (6.37 mWh cm−3) at a power density of 4.5 mW cm−2 (62.5 mW cm−2). Therefore, this work provides a proof-of-concept design for the high-performance supercapacitor electrode with carbon cloth substrate. [Display omitted]