Ultrathin Ni_1−xCo_xS₂ nanoflakes as high energy density electrode materials for asymmetric supercapacitors

• Xiaoxiang Wang,
• Teng Wang,
• Rusen Zhou,
• Lijuan Fan,
• Shengli Zhang,
• Feng Yu,
• Tuquabo Tesfamichael,
• Liwei Su and
• Hongxia Wang

Beilstein J. Nanotechnol. 2019, 10, 2207–2216, doi:10.3762/bjnano.10.213

• energy density of 67.5 Wh·kg−1) and excellent cycling stability. This approach can be a low-cost way to mass-produce high-performance electrode materials for supercapacitors. Keywords: electrode materials; high energy density; in situ phase transformation; NiCo sulfide; supercapacitors; ultrathin

• nanoflakes, the results were compared with previously reported NiCo-based ASCs. The new device outperforms Ni3S2/CoNi2S4/NF//AC [41], NiCo2S4/graphene//AC [39], NiCo2S4/NCF//(OMC = ordered mesoporous carbon)/NCF [31], NiCo2O4//AC [17], NiCo-sulfide//AC [28] and NiCo-hydroxide//AC [42]. The EIS results of the