In situ growth of burl-like nickel cobalt sulfide on carbon fibers as high-performance supercapacitors

Abstract

NiCo2S4/CFP displayed good cyclability and high rate capability with a capacitance loss of 24.1% after 5000 cycles.

High Energy Density Asymmetric Supercapacitors From Mesoporous NiCo2S4 Nanosheets

“…Replacing oxygen with sulphur may create a more flexible structure with the elongation of chemical bonds, thus making it easier for electrons to transport in this tuned structure, which can further contribute to the enhancement of electrochemical performances of SCs [12]. Therefore, with much lower optical band gap energy and ~100 times higher conductivity than that of NiCo2O4 [13,14], spinel NiCo2S4 could be a more promising candidate material for pseudocapacitors.…”

“…Besides, it is noted that the ion-exchange reaction could adjust the composition, structure and properties, taking a great effect on the purity and morphology of the NiCo2S4 [15,16] and it seems hard to obtain pure spinel NiCo2S4 by directly reacting Ni 2+ and Co 2+ with S 2-. Some sulphides such as Na2S [8,14,[17][18][19], thiourea [20,21] and thioacetamide [9,14] have been employed to prepared NiCo2S4 recently, and excellent electrochemical performance was demonstrated. Unfortunately, the route to obtain pure spinel NiCo2S4 material following these multiple steps, such as transforming from urea-prepared precursor to NiCo2S4 with Na2S, as reported very recently, is extremely difficult, and impuries of Co9S8, CoS, etc can generally be found in those sample [10,18,19,22,23].…”

In situ grown cockscomb flower-like nanostructure of NiCo2S4 as high performance supercapacitors

“…Moreover, ternary metal sulfides such as NiCo 2 S 4 and CoNi 2 S 4 have emerged as promising class of active materials for SCs. Ternary metals possess multiple oxidation states to achieve richer redox activities compared to metal sulfides [14][15][16][17][18]. However, the use of NiCo 2 S 4 for electrodes still faces challenges such as attaining high capacity, long cycle stability, and high-rated performance.…”

Mixed Metal Sulfides for Electrochemical Energy Storage and Conversion

“…To well address the above-mentioned issues, an intriguing strategy is to grow electroactive materials on conductive current collectors. Recently, nanoarrays of MMSs have been directly grown on conductive substrates, such as NF, [30,[111][112][113][114][115][116] carbon cloth (CC), [65,117,118] carbon fiber paper (CFP), [73,119,120] and so on, to construct 3D electrodes. Such binder-free and conductive-agent-free integrated electrodes can avoid the "dead surface" and the tedious process in preparing traditional slurry-coating electrodes and significantly improve the utilization rate of electroactive materials.…”