NiCo2O4

This paper reports the first effective fabrication of a high-performance non-enzymatic glucose sensor based on activated carbon cloth (ACC) coated with reduced graphene oxide (RGO) decorated N-doped urchin-like nickel cobaltite (NiCo2 O4 ) hollow microspheres. Hierarchically mesoporous N-doped NiCo2 O4 hollow microspheres were synthesized using a facile solvothermal method, followed by thermal treatment in a nitrogen (N2 ) atmosphere. Subsequently, they were hydrothermally decorated with RGO nanoflakes. The resulting composite was dip-coated onto ACC, and its electrochemical and glucose sensing performances were investigated using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and chronoamperometric measurements in a three-electrode system...

Forming semiconductor heterojunctions is a promising strategy to boost the efficiency of solar-driven photoelectrochemical (PEC) water splitting by accelerating the separation and transport of photogenerated charge carriers via an interfacial electric field. However, there is limited research considering the influence of electrolytes on the band alignment of the heterojunction under PEC conditions. In this work, we use a single crystal NiCo2 O4 /SrTiO3 (NCO/STO) heterojunction with atomic-precision controlled thickness as a model photoelectrode to study the band structure modulations upon getting in contact with the electrolyte and the correlation with the PEC activity...

The electrochemical performance of NiCo2 O4 with urea precursors was evaluated in order to develop a non-enzymatic urea sensor. In this study, NiCo2 O4 nanostructures were synthesized hydrothermally at different concentrations of urea and characterized using scanning electron microscopy and X-ray diffraction. Nanostructures of NiCo2 O4 exhibit a nanorod-like morphology and a cubic phase crystal structure. Urea can be detected with high sensitivity through NiCo2 O4 nanostructures driven by urea precursors under alkaline conditions...

The reasonable design and controlled synthesis of efficient and hollow nanocatalysts with plentiful heterointerface and fully exposed active sites to accelerate the electron transfer and mass transfer process for oxygen evolution reaction (OER) is highly desirable for water splitting by electrolysis. Herein, a metal-organic framework (MOF)-engaged strategy is developed to prepare Ce-doped hollow mesoporous NiCo2O4 nanoprisms (NiCo2O4/CeO2 HNPs) for enhanced OER. Due to the advanced synthesis strategy generating a large number of interfaces between NiCo2O4 and CeO2, as well as modulated electrons of the active center by the synergistic action of multi-metals, the obtained catalyst exhibits excellent OER performance with a small overpotential of 290 mV at current density (J) of 10 mA cm-2...

The oxide-based systems often suffer from higher overpotentials compared to transition metal sulphides and phosphides for the electrochemical hydrogen evolution reaction. Interestingly, the generation of oxygen vacancy has been seen as strategy for further activating transition metal oxides (NiCo2O4 as a model system) for electrochemical watersplitting. Herein, we employ the temperature ramp strategy (ambient air calcination) for the generation of oxygen vacancies in NiCo2O4 (NCO) towards tuning of electrocatalytic enhancements...

Along with the rapid development and ever-deepening understanding of nanoscience and nanotechnology, nanomaterials hold promise to mimic the highly evolved biological exquisite nanostructures and sophisticated functions. Here, inspired by the ubiquitous antibacterial nanostructures on the wing surfaces of some insects, a NiCo2 O4 nanozyme with self-adaptive hierarchical nanostructure is developed that can capture bacteria of various morphotypes via the physico-mechanical interaction between the nanostructure and bacteria...

Compression-tolerant electrodes are critical for developing next-generation wearable energy storage devices. However, most of previous studies on compressible electrodes focus on carbon-based materials, whereas metal-based materials such as spinel metal oxide with faradaic nature have been rarely studied due to their lack of compressibility. Herein, NiCo2 O4 (NCO) microtubes assembled by ultrathin and mesoporous nanosheets, are deposited on/into Ti3 C2 Tx MXene/reduced graphene oxide aerogel (MGA), an intrinsically compressible host template with high conductivity and specific surface areas...

The demands for alternative energy have led researchers to find effective electrocatalysts in fuel cells and increase the efficiency of existing materials. This study presents new nanocatalysts based on two binary transition metal oxides (BTMOs) and their hybrid with reduced graphene oxide for methanol oxidation. Characterization of the introduced three-component composite, including cobalt manganese oxide (MnCo2 O4 ), nickel cobalt oxide (NiCo2 O4 ), and reduced graphene oxide (rGO) in the form of MnCo2 O4 /NiCo2 O4 /rGO (MNR), was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray (EDX) analyses...

The development of responsive materials in a predictable manner is high on the list of the material industry's trends. In this work, responsive Ag@NiCo2 O4 nanowires were, firstly, anchored on N-doped carbon cloth (NC) and, then, employed as array electrodes for a nonenzymatic glucose-sensing application. The results showed that the highly conductive NiCo2 O4 nanowires supported Ag nanoparticles and exhibited high conductivity and electrocatalytic properties. The fully exposed crystalline planes of Ag nanoparticles provided more active surface sites...

The current work was performed to construct a novel electrochemical sensing system for determination of sunset yellow via the modification of screen-printed graphite electrode modified with hierarchical flower-like NiCo2 O4 nanoplates (NiCo2 O4 /SPGE). The prepared material (hierarchical flower-like NiCo2 O4 nanoplates) was analyzed by diverse microscopic and spectroscopic approaches for the crystallinity, composition, and morphology. Chronoamperometry, differential pulse voltammetry, linear sweep voltammetry, and cyclic voltammetry were used for determination of the electrochemical behavior of sunset yellow...

Herein, a 3D hierarchical structure is constructed by growing NiCo2 O4 nanowires on few-layer Ti3 C2 nanosheets using Ni foam (NF) as substrate via simple vacuum filtration and solvothermal treatment. Ti3 C2 nanosheets are directly anchored on NF surface without binders or surfactants, and NiCo2 O4 nanowires composed of about 15 nm nanoparticles uniformly grow on Ti3 C2 /NF skeleton, which can provide abundant active sites and ion diffusion pathways for enhancing electrochemical performance. Benefiting from the unique structure feature and the synergistic effects of active materials, NiCo2 O4 /Ti3 C2 exhibits a high specific capacitance of 2468 F g-1 at a current density of 0...

Microbial electrochemical systems (MESs) can harvest bioelectricity from varieties of organic matter in wastewater through electroactive microorganisms. Oxygen reduction reaction (ORR) in a cathode plays an important role in guaranteeing high power generation, which can be enhanced by cathode catalysts. Herein, the tiny crystalline grain nanocrystal NiCo2 O4 is prepared via the economic method and utilized as an effective catalyst in air-cathode MESs. The linear sweep voltammetry results indicate that the current density of 2% nano-NiCo2 O4 /AC cathode (5...

The large-scale fabrication of highly efficient and low-cost bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical to the development of rechargeable zinc-air batteries (ZABs). Herein, a scalable dealloying strategy was proposed to obtain hierarchically porous spinel-type oxide with minor hereditary Al doping. Benefiting from the well-structured porosity and native dopant, O-np-Ni5 Co10 (Al), namely Al-NiCo2 O4 , exhibited excellent electrocatalytic ORR and OER activities, giving a small potential gap of 0...

Multichannel-porous carbon derived from wood can serve as a conductive substrate for fast charge transfer and ion diffusion, supporting the high-theory capacitance of pseudocapacitive materials. Herein, NiCo2 O4 nanosheets, which are hierarchically porous, anchored on the surface of carbonized wood via electrodeposition for free-binder high-performance supercapacitor electrode materials, were proposed. Benefiting from the effectively alleviated NiCo2 O4 nanosheets accumulation and sufficient active surface area for redox reaction, a N-doped wood-derived porous carbon-NiCo2 O4 nanosheet hybrid material (NCNS-NCW) electrode exhibited a specific electric capacity of 1730 F g-1 at 1 A g-1 in 1 mol L-1 KOH and splendid electrochemical firmness with 80% capacitance retention after cycles...

Generally, C3N4 was widely used in the field of photocatalytic hydrogen production, but only few studies focused on electrocatalytic hydrogen production field in Ni/Co based systems. Herein, to investigate the enhanced HER property of C3N4, NiCo2O4@C3N4 were fabricated successfully via a simple mixture method. With the introduction of C3N4, NiCo2O4@C3N4 showed better HER property with small overpotential (89 mV, η10 mA cm-2), low Tafel slope (146 mV dec-1) and superior long-term stability, thereby indicating the excellent synergistic effect between NiCo2O4 and C3N4...

Catalytic hydrogenolysis of biobased furan aldehydes (i.e. 5-methylfurfural, 5-hydroxymethylfurfural) to 2,5-dimethylfuran has gained extensive interest for biomass-derived fuels and chemicals. Herein, a class of NiCo 2 O 4 supported palladium with considerable oxygen defects was synthesized by hydrogen plasma etching and phosphating methods. The oxygen defects not only promote the hydrogenation of C=O group but also enhance the accessibility of coordinatively unsaturated metal cations with Lewis acidity for the hydrogenolysis of the C-OH group...

We developed a novel hydroxylamine sensor through the surface modification of screen-printed electrode (SPE) with NiCo2 O4 nanoparticles/reduced graphene oxide (RGO) nanocomposite (NiCo2 O4 /RGO/SPE). We assessed the electrochemical response of hydroxylamine on the as-fabricated sensor, confirming the high electrocatalytic impact of hydroxylamine oxidation. The electrode produced sensitively responded to hydroxylamine under optimized conditions, with a low limit of detection (2.0 nM) and broad linear dynamic range (0...

2D metal oxide-based nanomaterials have emerged as an exciting area of research owing to their rich electrochemical properties and diverse applications, including biosensors. In this work, we have synthesized ultra-thin Co3 O4 , NiO, and NiCo2 O4 nanostructures supported on a carbon cloth and printed graphite/Kapton substrates following thermal reduction of self-assembled metal alkanethiolates. These nanostructures act as a sensing platform for simultaneous detection of dopamine (DA) and uric acid (UA), important biological molecules in physiological and pathological tests...

Herein, the Co3 O4 /NiCo2 O4 nanocomposite has been prepared as a novel electrochemical sensor to accurately detect hydrogen peroxide (H2 O2 ) and glucose. ZIF-67 is a metal-organic framework (MOF) with Co as the center metal ion. Co3 O4 can be obtained by calcination of ZIF-67 at 700 °C, which can retain the structure of ZIF-67. The hollow Co3 O4 nanocrystal was synthesized based on a calcination process of ZIF-67. This open structure can promote the whole Co3 O4 /NiCo2 O4 nanocomposite larger accessible surface area and reactive sites...

The oxygen evolution reaction (OER) plays a key role in determining the performance of overall water splitting, while a core technological consideration is the development of cost-effective, efficient, and durable catalysts. Here, we demonstrate a robust reduced Fe-oxide@NiCo2 O4 bilayered non-precious-metal oxide composite as a highly efficient OER catalyst in an alkaline medium. A bilayered oxide composite film with an interconnected nanoflake morphology (Fe2 O3 @NiCo2 O4 ) is reduced in an aqueous NaBH4 solution, which results in a mosslike Fe3 O4 @NiCo2 O4 (reduced Fe-oxide@NiCo2 O4 ; rFNCO) nanostructured film with an enhanced electrochemical surface area...