High Energy Density Asymmetric Supercapacitors From Mesoporous NiCo2S4 Nanosheets

Facile synthesis of CoNi 2 S 4 /Co 9 S 8 composites as advanced electrode materials for supercapacitors

“…As shown in Fig 4a, the nitrogen adsorption-desorption isotherm belongs to Langmuir H4 type isotherm that has an obvious hysteresis loop in the range of 0.6-1 relative pressure, which indicates the mesoporous characteristic of the sample [39]. The BET specific surface area of the sample is calculated to be 57.9 m 2 /g, which is larger than most of the reported values [35,[39][40]42]. The pore size distribution estimated by BJH method mainly distributes in the range of 1~4 nm and centered at 2.5 nm, suggesting its large specific surface area.…”

Low temperature fabrication of hydrangea-like NiCo2S4 as electrode materials for high performance supercapacitors

“…3b) exhibits sharp size distribution ranging from 1 to 4 nm and the pore radius centered at 1.9 nm, which is ideal size for ion transports. Besides, the BET surface area can be calculated to be 74.8 m transition to NiSOH, CoSO, CoSOH [11] and [12]. With the increasing scan rate, the anodic peaks shift towards higher potential and the cathodic peaks shift towards lower potential which is induced by greater electric polarization [7].…”

“…In general, the hydrothermal synthesis of NiCo 2 S 4 by method is conducted at relatively high temperature from 140 °C to 200 °C [11][12][13]. Nevertheless, the energy efficiency, security and reliability are compromised by the high temperature.…”

Mixed Metal Sulfides for Electrochemical Energy Storage and Conversion

“…[130] On the other hand, mesoporous structures with large specific surface area and appropriate pore size distribution are also expected to provide more active sites for electrochemical reactions, short path length for electron and ion transport, and efficient penetration of the electrolyte. [74,100,101,129] In this regard, Zhu et al developed a one-pot solvothermal method to synthesize 3D mesoporous NiCo 2 S 4 nanoparticles in ethylene glycol. [101] With pore size distribution in the range of 3-5 nm, the mesoporous NiCo 2 S 4 displays a specific surface area of 42.79 m 2 g −1 .…”

“…Ternary nickel cobalt sulfides with various crystal structures (such as NiCo 2 S 4 , [27,33,74,103,108,121] CoNi 2 S 4 , [93,98,111,117] Ni 1.5 Co 1.5 S 4 , [122] Co 0.9 Ni 0.1 S 2 , [123] Ni 3.5 Co 3.5 S 8 , [88] and Ni 3 Co 6 S 8 [124] ) and diverse nanostructures (such as nanoparticles, [92][93][94][95][96] nanotubes, [99] nanosheets, [100] and hierarchical porous/hollow nanostructures [28,74,75,79,83,99,[103][104][105][125][126][127][128] ) have been widely investigated and proved to possess superior electrochemical performance for energy storage and conversion. In this section, the application of nanostructured ternary nickel cobalt sulfides in HSCs, LIBs/SIBs, and electrocatalysis will be thoroughly summarized and discussed.…”