Design on hierarchical P doped Ni(OH)2@Ni–Co LDH core-shell heterojunction as an advanced battery-like electrode for high performance hybrid supercapacitors

• Published in: Journal of alloys and compounds 2020-03, Vol.817, p.152712, Article 152712
• Main Authors: Li, Kunzhen, Liu, Mengjie, Li, Shikuo, Huang, Fangzhi, Wang, Lei, Zhang, Hui
• Format: Article
• Language: English
• Subjects: Activated carbon; Capacitance; Core-shell heterojunction; Electrodes; Flux density; Heterojunctions; Hybrid supercapacitor; Light emitting diodes; Metal foams; Nickel compounds; Ni–Co LDH nanoflakes; P doped Ni(OH)2 rods; Structural hierarchy; Supercapacitors
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.152712

Designing reasonable composited material with optimized structures for high-performance electrodes have aroused widespread concern. Herein, we report a P doped Ni(OH)2@Ni–Co LDH arrays with core-shell hierarchical structure are in-situ grown on the 3D Ni foam (PNH@N–C LDH/NF). Benefiting from this unique core-shell heterojunction and the synergetic effect inducing by hexagon-like P doped Ni(OH)2 (PNH) rods with ultrathin N–C LDH nanoflakes, the tremendous areal specific capacitance of the binder-free electrode is about 6.05 C cm−2 at 1 mA cm−2, which is nearly 3.8 folds of the PNH/NF (1.59 C cm−2) electrode. And the electrode presents an extra-long cycle life (124% remained after 10000 cycles). Additionally, PNH@N–C LDH cathode, activated carbon anode with PVA/LiOH gel electrolyte are assembled to an all-solid-state hybrid supercapacitor (AHS). Meanwhile, the obtained AHS also exhibits an excellent energy density of 0.323 mWh cm−2 (power density is 1.6 mW cm−2) and outstanding cycling stability (87.9% initial capacitance after 4500 cycles). Moreover, the two AHS (each about 1 cm2) can easily light up three LEDs for 10 min. In our study, the general, cost-effective, and eco-friendly synthesis process of PNH@N–C LDH is provided an attainable strategy to prepare promising self-supporting electrode for the potential applications in the future of electronic equipments. A novel P–Ni(OH)2@Ni–Co LDH grown on porous Ni foam as high-performance self-supporting supercapacitors electrode was firstly designed and synthesized with core-shell heterostructure, high power and energy density of hybrid supercapacitors were achieved and has a great prospective in future energy storage devices. [Display omitted] •A novel P doped Ni(OH)2@Ni–Co LDH nanoarrays was firstly designed and synthesized.•It delivers an ultrahigh areal specific capacitance of 6.05 C cm−2 at 1 mA cm−2.•The hybrid device has outstanding cycling stability.•The nanoarrays has a great prospective application in energy storage devices.