Synthesis of mesoporous NiCo 2 S 4 deposited on reduced graphite oxide assistant by co-polymer Pluronic F127 for high-performance supercapacitor

NiCo2S4‐Based Composite Materials for Supercapacitors

“…Graphene and reduced graphene oxide (rGO) are two‐dimensional (2D) carbon materials with high surface area and excellent electrical conductivity, and has been in depth studied for supercapacitor applications . Previous works have indicated that the performances of supercapacitors can be significantly enhanced by fabricating nanocomposites using graphene or rGO with other functional materials …”

Electrostructural Compatibility of Battery-Type Diffuse-Porous Co9S8–NiCo2S4/Defective Reduced Graphene Oxide and Flaky FeS/Nitrogen-Doped Defective Reduced Graphene Oxide for Ultra-High-Performance All-Solid-State Hybrid Pseudocapacitors

“…48 The largely broad deconvoluted peaks at 168.53 and 169.87 eV correspond to the oxidized sulfur (sulfate) species which might be generated due to the continuous exposure of the material to atmospheric air. 49 The deconvoluted spectrum of C 1s is presented in Figure 2E, which shows three major peaks at binding energies of 284.39, 285.49, and 287.88 eV, which validate the existence of carbon in Co 9 S 8 −NiCo 2 S 4 /D-rGO in three different chemical environments. The deconvoluted peaks at binding energies of 284.39, 285.49, and 287.88 eV are attributed to the carbon atoms bonded to sulfur (C−S−C), carbon atoms bonded together (C�C) in the aromatic ring of graphene, and sp 2 hybridized carbon atom from rGO to oxygen (C�O), respectively.…”

“…The deconvoluted peaks at binding energies of 284.39, 285.49, and 287.88 eV are attributed to the carbon atoms bonded to sulfur (C−S−C), carbon atoms bonded together (C�C) in the aromatic ring of graphene, and sp 2 hybridized carbon atom from rGO to oxygen (C�O), respectively. 49 The appearance of the XPS peak corresponding to C�O substantiates that the rGO surface is very much functionalized, which is categorically due to the presence of the additional concentration of defective sites on the rGO surface, as established in the FT-Raman analyses. 22 10 The higher magnification HRTEM image in Figure 4B shows individual crystallites of Co 9 S 8 −NiCo 2 S 4 which are interconnected with each other, resulting in the inherent diffuse porosity.…”

Controlled Synthesis of NixCoyS4/rGO Composites for Constructing High-Performance Asymmetric Supercapacitor

“…Specifically, the peaks at 853.5 and 870.8 eV in Ni 2p correspond to Ni 2+ , and the peaks at 857.7 and 875.5 eV can be assigned to Ni 3+ , confirming the coexistence of both Ni 2+ and Ni 3+ in the composite. Similarly, the peaks located at 779.0 eV, 794.1 eV in Co 2p corresponds to the Co 3+ , and the peaks at 782.2 eV, 798.8 eV of Co 2p spectrums associates to the Co 2+ , suggesting the coexistence of Co 3+ and Co 2+ in Ni 1.64 Co 2.40 S 4 /rGO composite as well (Fan et al, 2017;Qin et al, 2017). For the S 2p spectrum, the peak located at 161.8 eV for S 2p 3/2 is attributed to S 2− or C-S-C bonds on the surface (Chen X. et al, 2014), while the peak at 162.9 eV for S 2p1/2 can be ascribed to S-M (metal) bonds.…”

“…Furthermore, the C 1s spectrum exhibits a major peak at 284.7 eV attributed to C-S-C bonds (Wenfang et al, 2015). Additionally, a peak located at 285.9 eV in the C 1s spectra corresponds to the C=C bond (aromatic-linked carbon), while the weak peak at 289.2 eV can be ascribed to the carboxyl groups (C=O) and sp 2 hybridized carbon from rGO, the low strength of the peak at 289.2 eV also indicates that the graphene has been reduced (Qin et al, 2017). The S 2p and C 1s XPS results reveal the existence of S-M (M=Ni or Co) and C-S-C bonds, respectively, which verifies the doping of S into rGO and the formation of transition metal sulfides in the composite material.…”