Treatment of NiMoO4/nanographite nanocomposite electrodes using flexible graphite substrate for aqueous hybrid supercapacitors

Abstract

The cycling performance of supercapacitors sometimes becomes limited when electrode materials slough off during frequent charge–discharge cycles, due to weak bonding between the active material and the current collector. In this work, a flexible graphite foil substrate was successfully used as the current collector for supercapacitor electrodes. Graphite foil substrates were treated in different ways with different acid concentrations and temperatures before being coated with an active material (NiMoO4/nanographite). The electrode treated with HNO3 (65%) and H2SO4 (95%) in a 1:1 ratio at 24°C gave better electrochemical performance than did electrodes treated in other ways. This electrode had capacitances of 441 and 184 Fg–1 at current densities of 0.5 and 10 Ag-1, respectively, with a good rate capability over the current densities of the other treated electrodes. SEM observation of the electrodes revealed that NiMoO4 with a morphology of nanorods 100–120 nm long was properly accommodated on the graphite surface during the charge–discharge process. It also showed that treatment with high-concentration acid created an appropriately porous and rough surface on the graphite, enhancing the adhesion of NiMoO4/nanographite and boosting the electrochemical performance.

Low-temperature microwave hydrothermally synthesized Mn-doped NiCo2O4 nanoparticles: enhanced structural and electrochemical properties

“…5(f) from which reveals the has highest specific capacitance for the sample x = 0.06, and the same were tabulated in Table 3. From the table, it was also observed that the specific capacitance decreases with an increase in scan rate because faster redox reactions take place at a higher scan rate, reducing electrolyte ion diffusion into the material and consequently lowering the capacitance [35]. Using the GCD test, the specific capacitance (Csp), energy density (Ed), and power density (Pd) were calculated by adopting the expressions [36].…”

From energy storage to pathogen eradication: unveiling the antibacterial and antiviral capacities of flexible solid-state carbon cloth supercapacitors

“…Such decrease is related to diffusion limitations of electrolyte in pores of electrode material. 33,67,68 However, 83% of the areal capacitance calculated from the CV obtained at the scan rate of 5 mV s À1 was preserved at the scan rate of 100 mV s À1 , indicating a good high-rate capability of the CCSCs (Fig. 3E).…”

Recent developments and future perspectives on energy storage and conversion applications of nickel molybdates

“…This is so because this strategy offers the most convenient processes and yet conducive outcomes. Table 6 is to impart a brief account of a host of developments in catalytic properties of NiMoO 4 done involving heterostructures and hybrids 121,123,256‐382 . in many cases, doping, defect and/or morphology engineering have been amalgamated with the heterostructure for superior enhancement in catalytic properties either to generate more surface area or more population of active sites or for other special necessities as summarized in Table 6.…”

“…Table 10 is to summarizes a few notable works pertaining to improvement in supercapacitor performance by employing NiMoO 4carbon-based composites. 202,226,256,259,266,270,277,280,285,287,290,297,310,316,320,326,330,337,344,347,348,[350][351][352]356,363,372,374,380,381,390…”

“…Like in the case of supercapacitors, a range of CNMs have been witnessed to upgrade electrochemical catalytic properties of NiMoO 4 while heterostructure is fabricated. Table 13 briefs a few such interesting findings focusing 202,226,256,259,266,270,277,280,285,287,290,297,310,316,320,326,330,337,344,347,348,356,363,372,374,380,381,390 Material/condition on applications of NiMoO 4 in the battery. 169,262,276,280,299,302,309,315,316,342,349,356,359,364 Graphene being an excellent conductor is a suitable choice for enhancement in performance while coupled with NiMoO 4 .…”