Nickel Cobalt Research Articles

Enhanced performances of NiCoSe2 electrode coated with Ag nanoparticles by magnetron sputtering for the applications of asymmetric supercapacitors

In this work, a binder-free energy-storage electrode material of Ag nanoparticles coated nickel cobalt selenide (NiCoSe2) on Ni foam (NF) was first proposed. Wherein, NiCoSe2 was synthesized by one-step hydrothermal method using ascorbic acid as reductant, and the coating of Ag nanoparticles on NiCoSe2 were performed by magnetron sputtering method. The specific surface area was greatly increased due to the deposited Ag nanoparticles, and in this way the impedance of the electrode decreased, and the electrochemical properties were enhanced. When the magnetron sputtering time is 10 s, Ag/NiCoSe2 electrode exhibits the most excellent performances. However, further increase of sputtering time may result in the over cover on NiCoSe2, with great deterioration in electrochemical behavior. Single NiCoSe2 electrode possesses an area capacitance of 1600.7 mF cm−2 at a current density of 2 mA cm−2, while Ag/NiCoSe2 electrode could reach up to 2280 mF cm−2. The asymmetric supercapacitor (ASC) assembled by Ag/NiCoSe2 and activated carbon (AC) electrodes shows a high energy density of 0.171 mWh cm−2 as well as a power density of 17.340 mW cm−2, and the cyclic stability remains at 90.1% after 4000 cycles, which is superior to 83.7% of the NiCoSe2 single electrode.

Sonochemically synthesized novel CNTs-PANI/CoNi(PO4)2 nanocomposites with enhanced electrochemical energy storage performance for asymmetric supercapacitor applications

Carbon nanotubes (CNTs) were polymerized with polyaniline (PANI) via an in-situ polymerization approach. These functionalized CNTs (PANI-CNTs) were added in various concentrations to the sono-chemically synthesized Co-Ni binary transition metals phosphate (CoNi(PO4)2) to ultimately have their nanocomposites. Electron microscopy (SEM & HRTEM) was employed to reveal the morphology and microscopic features. The structural evaluation of metal phosphate and PANI/CNTs was done by X-ray diffractometer analysis, whereas chemical grafting of cobalt nickel phosphate (CoNi(PO4)2) was done by Fourier transformed infrared spectroscopy and Raman spectroscopy. The hierarchical structured CoNi(PO4)2 with 40 mg PANI/CNTs mass (CNP40) presented enhanced specific capacity of 1268 Cg−1 (2136 F g−1 at 1.5 F g−1) with excellent diffusive behavior (b = 0.5). A resulted hybrid supercapacitor device consisting of CNP40 as +ve electrode and activated carbon AC) as −ve electrode, presented excellent energy density of ∼87 Whkg−1 with good power density of 680 W kg−1 maintained to 32.9 W kg−1 (@ 20,400 W kg−1) with 37% rate performance, and excellent cyclic performance (∼100%) after 5000 charge-discharge cycles. Furthermore, capacitive-diffusive analysis revealed that the device showed 55% diffusive and 45% capacitive behaviour. This improved electrochemical performance might be attributed mainly to the uniform and hierarchical chemical grafted morphology of the novel combination of binary phosphates and PANI functionalized CNTs in the nanocomposite obtained via a rather different sonochemical approach.

Coaxial nickel cobalt selenide/nitrogen-doped carbon nanotube array as a three-dimensional self-supported electrode for electrochemical energy storage.

Herein, we propose a one-step urea pyrolysis method for preparing a nitrogen-doped carbon nanotube array grown on carbon fiber paper, which is demonstrated as a three-dimensional scaffold for constructing a nickel cobalt selenide-based coaxial array structure. Thanks to the large surface area, interconnected porous structure, high mass loading, as well as fast electron/ion transport pathway of the coaxial array structure, the nickel cobalt selenide/nitrogen-doped carbon nanotube electrode exhibits over 7 times higher areal capacity than that directly grown on carbon fiber paper, and better rate capability. The cell assembled by a nickel cobalt selenide/nitrogen-doped carbon nanotube positive electrode and an iron oxyhydroxide/nitrogen-doped carbon nanotube negative electrode delivers a volumetric capacity of up to 22.5 C cm-3 (6.2 mA h cm-3) at 4 mA cm-2 and retains around 86% of the initial capacity even after 10 000 cycles at 10 mA cm-2. A volumetric energy density of up to 4.9 mW h cm-3 and a maximum power density of 208.1 mW cm-3 are achieved, and is comparable to, if not better than, those of similar energy storage devices reported previously.

A sustainable synthesis, characterization of modified waste onion peels and its exploration in various applications

The modification of waste to a bio-based material that is economical, environmentally sustainable, and extremely effective is crucial for organic conversions. For bio waste, that doesn’t decompose easily and have bad impact on environment such as onion peels, a suitable method is introduced which focuses on utilizing onion peels, a commonly discarded agricultural waste, as a valuable resource for antibacterial studies and bio sensing of heavy metals. A comparative study to analyse these properties were done using onion peel extract and saponified onion peels. The saponified material was obtained by treating onion peels (Allium cepa) with sodium hydroxide in the presence of calcium carbonate. The popularity of saponification reaction and saponified material is rising because of their special qualities and uses as disinfectants, surfactants, antifungal agents, in drugs for target based delivery etc. The saponified onion peels was analyzed by FTIR (Fourier transform infrared spectroscopy), and XRD (X-ray diffraction), EDX (energy-dispersive X-ray), SEM (scanning electron microscopy). Furthermore, against Bacillus subtilis (Gram positive), antibacterial activity of onion extract and saponified onion peels were studied. In comparative study onion peel extract shows better inhibition zone then saponified onion peels. Bio sensing of heavy metals were done by using these materials, onion peel extract shows visual colour change with Nickel chloride (NiCl2), Cobalt chloride (CoCl2), Potassium bromide (KBr), Manganese sulphate (MnSO4), Mercury chloride (HgCl2) and Copper sulphate (CuSO4) metal salts.

Synergistic interfacial electronic modulation of topotactically developed bimetallic CoNiP on NiS nanorods for enhanced alkaline hydrogen evolution reaction.

Designing hybrid transition metal phosphosulfide electrocatalysts is critical for the hydrogen evolution reaction (HER). We propose a novel approach by designing a hierarchical structure of cobalt phosphide (CoP) and nickel phosphide (Ni8P3) nanoparticles topotactically developed on nickel sulfide (Ni3S2) nanorods (CoNiP/NiS) via a sulfuration-phosphorization strategy using conductive 3D nickel foam. Hierarchical heterostructured nanorods were achieved without the need for template removal steps or the assistance of surfactants. This not only simplifies the process but also improves the exposure of active sites for catalytic purposes. Furthermore, the theoretical calculation results revealed that the high H* adsorption-free energy for CoP and Ni8P3 phases significantly decreases upon coupling with Ni3S2, which indicates that the interfacial electronic interaction synergistically modulates both CoP and Ni8P3 (CoNiP) at the coupled interfaces and facilitates the adsorption and desorption of H* intermediates during the HER process. The resulting electrode exhibits excellent performance in the HER catalytic process and shows great performance for further exploration in the urea oxidation reaction (UOR). Our work provides a stepping stone toward rational topotactic transformation of active materials on porous substrates, using electronic structure regulation and heterointerfaces to produce promising electrocatalysts for sustainable, large-scale hydrogen production from water electrolysis.

Catalytic ‘gelectrodes’ based on Co and Ni–Fe oxy/hydroxides for sustainable and enhanced oxygen evolution reaction

‘Gelectrodes’ based on nanocomposites of cobalt oxyhydroxide and nickel–iron hydroxide in chitosan on nickel foam are developed, and their efficient mediation of the oxygen evolution reaction with high and sustainable current densities demonstrated.

Effect of Metal Surface Treatment on Bonding of Porcelain to Recycled Cobalt Chromium and Nickel Chromium

Effect of Metal Surface Treatment on Bonding of Porcelain to Recycled Cobalt Chromium and Nickel Chromium

Mitigating hydrogen gas evolution in high nickel cathodes using single-crystalline NCM particles

Single-crystal nickel cobalt manganese oxide cathodes significantly reduce hydrogen gas evolution due to their smaller specific surface area and enhanced structural stability.

A high-performance electrocatalyst via graphitic carbon nitride nanosheet-decorated bimetallic phosphide for alkaline water electrolysis.

Developing renewable and clean energy systems for overall water electrolysis requires low-cost, highly efficient, and stable catalysts. With this motivation, nickel cobalt phosphorus (NiCoP) was electrodeposited onto nickel foam (NF) and then modified with graphitic carbon nitride (g-C3N4). The designed g-C3N4/NiCoP/NF electrode was used for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline water electrolysis. It exhibited a small overpotential of 80 mV@10 mA cm-2 with a Tafel slope of 89 mV dec-1 for the HER. It also exhibited an overpotential of 370 mV@10 mA cm-2 with a Tafel slope of 64 mV dec-1 for the OER. The g-C3N4/NiCoP catalyst exhibited satisfactory stability in an alkaline electrolyzer system, in which g-C3N4/NiCoP/NF was used as the anode and cathode. Meanwhile, the electrocatalyst requires only a cell voltage of 1.70 V to achieve 10 mA cm-2 current density for overall water electrolysis.

A defective NiCo-pentlandite/black phosphorus heterostructure for efficient water splitting electrocatalysis

A defective nickel cobalt pentlandite/black phosphorus heterostructure achieves highly active and durable water electrolysis through interface and heteroatom dual-engineering.

Improving the composite-structured supercapacitor assembled with Ni–Co-layered double hydroxide and polymer cement electrolyte through structural optimization

The optimized nickel–cobalt double hydroxide electrode by electrodeposition has a high specific area capacitance of 10.53 F cm−2. Capacitors assembled using the optimized electrodes have a specific capacitance of up to 1.442 F cm−2.

Phosphorus doping of nickel–cobalt boride to produce a metal–metalloid–nonmetal electrocatalyst for improved overall water splitting

A phosphorus-doped nickel–cobalt boride (P-NCB) electrocatalyst designed based on a unique metal–metalloid–nonmetal configuration results in solitary structures with excellent bifunctional properties for the HER and OER under strongly alkaline conditions.

One-dimensional nickel–cobalt bimetallic phosphide nanostructures for the oxygen evolution reaction

Electrospun nickel–cobalt bimetallic phosphide nanofibers exhibited both enhanced electrocatalytic activity and excellent long-term stability for the OER.

ZIF-67-derived Co-N-C supported nickel cobalt sulfide as a bifunctional electrocatalyst for sustainable hydrogen production via alkaline electrolysis.

As non-renewable resources are finite and cannot be utilized indefinitely, hydrogen (H2) has emerged as a promising alternative for clean and sustainable energy. The cost-effective hydrogen production to meet large-scale commercial demand poses a significant challenge. Water electrolysis, powered by electricity derived from renewable resources, stands out as a viable route towards sustainable hydrogen production, with electrocatalysis playing a pivotal role in this process. Notably, materials derived from metal-organic frameworks (MOFs) exhibit excellent physicochemical properties, making them promising candidates for electrocatalysis. In this study, we synthesized zeolitic imidazolate framework-67 (ZIF-67) and its derived Co-N-doped carbon (Co-N-C) supported NiCo2S4 on nickel foam (NF), namely NF@ZIF-67@NiCo2S4 and NF@Co-N-C@NiCo2S4, using a hydrothermal method. The electrocatalytic activity of these synthesized materials for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) was systematically evaluated using various electrochemical techniques. The NF@ZIF-67@NiCo2S4 material demonstrates overpotentials of 248 and 359 mV for OER and HER at the current density of 50 mA cm-2, whereas, NF@Co-N-C@NiCo2S4 exhibits overpotentials of 239 and 351 mV, respectively. Furthermore, the catalysts exhibit excellent stability in both OER and HER even under high applied potentials. Moreover, to assess their catalytic performance in a full-cell configuration, two alkaline electrolyzer cells were assembled: NF@ZIF-67@NiCo2S4(+)∥NF@ZIF-67@NiCo2S4(-) and NF@Co-N-C@NiCo2S4(+)∥NF@Co-N-C@NiCo2S4(-). These two electrolyzers demonstrated cell potentials of 1.62 V and 1.59 V at 10 mA cm-2, respectively, showcasing their efficacy in overall water-splitting.

Electrochemical surface reconstruction of nickel cobalt pyrophosphate to Ni/Co-hydroxide-(oxy)hydroxide: an efficient and highly durable battery-type supercapacitor electrode material

Highly durable porous battery-type supercapacitor charge storage material derived through electrochemical surface reconstruction of nickel cobalt pyrophosphate.

Nanostructured nickel–cobalt alloy/rGO-SWCNT thin film as an efficient electrocatalyst for hydrogen evolution reactions

CoNi alloy on the surface of rGO-SWCNT can regulate the electron structure, promoting HER performance. CoNi21 alloy exhibited the most notable HER efficiency with an overpotential of 83.5 mV and 291.8 mV at 10 mA cm−2 and 100 mA cm−2, respectively.

Electrostatic self-assembled nickel cobalt sulfide/Ti3C2 Mxene as a bio-capacitive anode for specific attracting sulfur-cycling bacteria and regulating extracellular electron transfer efficiency

Microbial fuel cells have been proposed as one of the sustainable and potential technologies for treating contaminants and synchronously producing green energy. However, the poor performance of the anode is a major obstacle in the practical application of MFCs. To address this challenge, the rational design of anode materials with enhanced biocatalytic and biocompatible properties has been considered as an effective approach to improve extracellular electron transfer (EET) processes and general MFC performance. Herein, in light of the interaction between the transition metal and exoelectrogens, nickel-cobalt sulfide/Ti3C2 Mxene (NiCo2S4/Mxene) is prepared by electrostatic assembly, which combined positively charged sea-urchin-like NiCo2S4 with negatively charged Mxene. This not only prevents the stacking of NiCo2S4 and Mxene but also accelerates the EET process by harnessing their biocompatibility and biocatalyst. As expected, the MFC with NiCo2S4/Mxene harvested higher electricity energy (9.66 ± 0.28 W/m3), significantly exceeded those of plain carbon felt (CF, 1.68 ± 0.13 W/m3), Mxene (4.32 ± 0.20 W/m3) and NiCo2S4 (5.41 ± 0.22 W/m3). Moreover, the microbial community analysis further revealed that the sulfide composite attracts a higher percentage of sulfur-cycling exoelectrogens (Desulfuromonas (24.25%) and Marinobacterium (15.75%)), motivating associated metabolic pathways with more efficient electricity generation processes. Such commendable performances are mainly attributed to the synergistic effect between NiCo2S4 and Mxene, which confers the bioanode with good biocompatibility and biocatalyst for biofilm adhesion and colonization, as well as providing abundant transition metals and sulfide active sites for the EET process. Our finding provides a facile routine for developing sulfide with appropriate modification as anode material for favorable performance of MFC, providing insights for sustainable and cleaner energy production in the future.

Challenges and opportunities using Ni-rich layered oxide cathodes in Li-ion rechargeable batteries: the case of nickel cobalt manganese oxides

Doping, coating, surface modification, formation of composites and control of crystalline orientation can control the capacity retention of Ni-rich cathodes. Furthermore, the design of Co-free Ni-rich cathodes may provide a cost-effective solution.

Efficient leaching of valuable metals from NCM cathode materials by green deep eutectic solvent

The soaring surge in electric vehicle sales has led to a significant rise in the demand and production of lithium-ion batteries. Consequently, a considerable number of lithium-ion batteries are retired annually, posing potential environmental pollution and economic losses if not appropriately disposed. In consideration of the aforementioned, a novel and environmentally conscientious approach is posited for the extraction of valuable metals from lithium-ion battery cathode materials, thereby ensuring economic efficiency. The method in question employs a deep eutectic solvent composed of tetraethylammonium chloride and L-ascorbic acid, facilitating the effective leaching of lithium nickel cobalt manganate cathode material within a brief duration of 3 min, even at a relatively low temperature of 80 °C. Notably, elevated leaching rates, specifically 99.1% for lithium, 99.6% for nickel, 99.4% for cobalt, and 99.3% for manganese, have been attained. The overall leaching process is characterized by its efficiency, environmental friendliness, and ease of operation, presenting a promising solution for the recycling of waste lithium-ion batteries.

Selective synthesis of monodisperse bimetallic nickel–cobalt phosphates with different nanoarchitectures for battery-like supercapacitors

This work reports the selective synthesis of monodisperse nickel–cobalt phosphate particles with different structures for battery-like supercapacitors.