Details

Autor(en) / Beteiligte

• Cao, Zhanzhi
• Liu, Chunhua
• Huang, Yunxia
• Gao, Ya
• Wang, Yuan
• Li, Zhimin
• Yan, Yangxi
• Zhang, Maolin

Titel

Oxygen-vacancy-rich NiCo2O4 nanoneedles electrode with poor crystallinity for high energy density all-solid-state symmetric supercapacitors

Ist Teil von

• Journal of power sources, 2020-02, Vol.449, p.227571, Article 227571

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Cubic spinel phase NiCo2O4 nanoneedles with poor crystallinity are grown successfully on Ni foam (NF) substrate through annealing the precursor obtained via a facile hydrothermal approach. The poor crystallinity can promote the generation of oxygen vacancy defects, which lead to improve the electrical conductivity of NiCo2O4. As electrode of supercapacitors, NiCo2O4/NF exhibits an excellent specific capacitance of 1076 F g−1 at a current density of 0.5 A g−1 and better cyclic stability which the specific capacity is ~14% higher than that of the beginning after 1000 cycles at current density of 10 A g−1. The all-solid-state symmetric supercapacitor (SSC) based on NiCo2O4//NiCo2O4 electrodes delivers a high energy density of 30.5 W h kg−1 at a power density of 750 W k g−1. The results reveal that the poor crystallinity and the presence of oxygen vacancies are the important factors for improving the charge storage ability of NiCo2O4 electrode materials. [Display omitted] •Spinel NiCo2O4 nanoneedles with poor crystallinity were grown on Ni foam substrate.•Oxygen vacancies lead to improve the electrical conductivity of NiCo2O4.•NiCo2O4/NF reveals the high specific capacity and better cycling stability.•The all-solid-state SSC device delivers a high energy density of 30.5 W h kg−1.