Solvothermal Synthesis of Flower-Flakes Like Nano Composites of Ni-Co Metal Organic Frameworks and Graphene Nanoplatelets for Energy Storage Applications

Abstract

Solvothermal synthesis of Ni-Co-MOF/graphene nanoplatelets (GNPs) nanocomposites was done for their potential application as electrode material in energy storage devices. Addition of GNPs and metallic precursors together with 2-methylimedazole in the same autoclave reactor produced smooth-nanoflakes like Ni-Co-MOF/GNPs nanocomposites as evaluated by SEM. XRD analysis showed the presence of GNPs where GNPs do not affect the growth of MOF crystals and Ni-Co-MOF crystalline phases remain unaffected in the composite structure. FTIR analysis confirmed the presence of organic links forming nickel-cobalt metal cations framework. Electrochemical testing(CV,EIS,GCD) of the produced composites demonstrated that GNPs addition can enhance the charge storage performance of MOFs nanocomposites. The largest cycle area and most discharge time have been shown by Ni-Co-MOF/GNP-50 composite electrode that delivered the highest specific capacity values (313 Cg-1@1 Ag-1), good reversibility and low internal resistance and charge transfer resistance. Moreover, Ni-Co-MOF/GNP-50 composite exhibited good thermal stability with 28% weight loss during thermogravimetric analysis. The electrochemical evaluations performed on asymmetric supercapacitor real device expressed a specific capacity of 136.5 Cg-1@0.5 Ag-1, maximum energy density of 32.2 Whkg-1@425 Wkg-1 and maximum power density of 17000 Wkg-1@12.8 Whkg-1. Moreover, the device showed a stability performance of 92.5%@10 Ag-1 after 5000 CD cycles.

Comparison of In Situ‐Fabricated Ternary NiCoMn‐Metal–Organic Frameworks versus Slurry Deposition on Porous Ni‐Foam: A Facile Approach for Enhancing Supercapacitor Performance

“…Peaks appearing at 11 and 23°well matched with Ni-MOF. [50,51] While the peaks appearing at 33.5, 38.4, 45.3, and 60.8°represent the formation of NiCo-MOF well matched with literature. [50] Due to the formation of NiCoMn-MOF, the appearance of peaks at 34.1 and 59.5°o ccurred giving strong evidence of the successful formation of ternary NiCoMn-MOF.…”

Tailoring the Effect of NiCo‐Metal‐Organic Frameworks by Doping Manganese as a Highly Active Redox Electrode for Electrochemical Energy Storage Technologies: Supercapattery Devices

“…Figure 2 a demonstrates that the major intensity peaks are visible at 14.18°, 17.6°, 32.3°, 46.0°, 66.83°, and 75.77° for NiCoMOF, which correspond to the previously stated literature. [ 38,39 ] While the key peaks for NiCoMnMOF in XRD pattern were analyzed at 2 θ values of 12.8°, 16.27°, 25.7°, 33°, and 79° as elucidated in Figure 2e, [ 40 ] a clear shift in XRD peaks for the samples containing Mn doping was observed, showing strong evidence of a successful doping mechanism when compared to its counterpart, that is, NiCoMOF. Furthermore, the FTIR spectrum of the generated structures within frequency limit of 650–4000 cm −1 is shown in Figure 2b.…”

“…[63] To evaluate ESDs, specific energy (E s ) and power (P s ) are valuable parameters. [39] Therefore, energy and power densities were calculated for the NiCoMn─ MOF//AC hybrid using relevant equations.…”

“…[ 63 ] To evaluate ESDs, specific energy ( E s ) and power ( P s ) are valuable parameters. [ 39 ] Therefore, energy and power densities were calculated for the NiCoMnMOF//AC hybrid using relevant equations.…”

“…Transition metal sulfides, oxides, phosphates, and phosphides are extensively studied as working electrodes for energy storing purposes. [ 18,19 ] However, the search for advance materials remains an ongoing and continuous process. [ 20 ] In this context, the combination of distinct oxides can greatly enhance the electrochemical features by optimizing synergistic effects that arise among the various oxides.…”