Defect-Engineered Nanostructured Ni/MOF-Derived Carbons for an Efficient Aqueous Battery-Type Energy Storage Device

Abstract

A Ni-based metal–organic framework (Ni-MOF) has been synthesized using a microwave-assisted strategy and converted to nanostructured Ni/MOF-derived mesoporous carbon (Ni/MOFDC) by carbonization and acid treatment (AT-Ni/MOFDC). The materials are well characterized with Raman, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET), revealing that chemical etching confers on the AT-Ni/MOFDC-reduced average nanoparticle size (high surface area) and structural defects including oxygen vacancies. AT-Ni/MOFDC displays low series resistances and a higher specific capacity ( C s ) of 199 mAh g –1 compared to Ni/MOFDC (92 mAh g –1 ). This study shows that the storage mechanism of the Ni-based electrode as a battery-type energy storage (BTES) system can be controlled by both non-faradic and faradic processes and dependent on the sweep rate or current density. AT-Ni/MOFDC reveals mixed contributions at different rates: 75.2% faradic and 24.8% non-faradic contributions at 5 mV s –1 , and 34.1% faradic and 65.9% non-faradic at 50 mV s –1 . The full BTES device was assembled with AT-Ni/MOFDC as the cathode and acetylene black (AB) as the anode. Compared to recent literature, the AT-Ni/MOFDC//AB BTES device exhibits high energy (33 Wh kg –1 ) and high power (983 W kg –1 ) with excellent cycling performance (about 88% capacity retention over 2000 cycles). This new finding opens a window of opportunity for the rational designing of next-generation energy storage devices, supercapatteries, that combine the characteristics of batteries (high energy) and supercapacitors (high power).

Bifunctional Behavior of Pd/Ni Nanocatalysts on MOF‐Derived Carbons for Alkaline Water‐splitting

“…After annealing and subsequently etched, it produces Ni‐rich and ‐deficient composites, respectively, with similar diffraction patterns observed. The double Bragg angle (2θ) value at 26.3° (002) ascribable to the hexagonal graphitic carbon, whereas the diffraction peaks at 44.9, 52.1, 76.7, 93.1, and 98.4°, corresponding to Ni(111), Ni(200), Ni(220), Ni(311), and Ni(222), respectively, with face‐centered cubic symmetry of Ni [21]. Although, the diffraction pattern of the Ni‐deficient composite became broader, suggesting that chemical etching induced some defects and strains in the crystal lattice with perhaps reduced crystallize size.…”

“…The improved electrocatalytic activities of Pd materials with the co-metal catalyst composites inspired the interests to synthesize novel co-metal catalyst composite from metal-organic frameworks (MOFs) because of their unique properties like tunable porosity and structure and high surface area [18]. The MOFs are emerging unique porous materials that are being explored as sacrificial templates for making carbon composites with impressive performances in electrocatalysis and energy storage [19][20][21]. The MOF template was made from nickel (Ni) metal because of its potential to enhance water electrolysis [22].…”

Carbon Encapsulated Ternary Mn−Ni−Co Oxide Nanoparticles as Electrode Materials for Energy Storage Applications

“…Galvanostatic charge‐discharge experiments of the samples were measured to further explore their potential application. The specific capacity of the electrode calculated from the charge‐discharge curves is obtained from the three electrodes testing using the following relation [46, 48]: …”

Experimental and Theoretical Studies on the Protective Effect of a Biomass Corrosion Inhibitor (vigna radiata) on Mild Steel in Acidic Medium

“…The circuit model shown comprises of a single CPE and charge transfer resistance elements which denote the impedance effect as a result of corrosion product species for the uninhibited environment. In this circuit, the CPE was used as a replacement for pure capacitance to recompense for the electrode surface unevenness frequently initiated by the buildup of corrosion products and lack of uniformity of the metal surfaces [29,30] including surface micro-defects. The use of such CPE affords insight for the nonconformities from ideal dielectric behavior.…”