NiCo Layered Research Articles

A Systematic Study of NiCo Layered Double Hydroxides Grown on Porous Carbon for Hybrid Battery-like Supercapacitor Electrodes: Growth Method, Morphology, and Composition

A Systematic Study of NiCo Layered Double Hydroxides Grown on Porous Carbon for Hybrid Battery-like Supercapacitor Electrodes: Growth Method, Morphology, and Composition

Corrosion behavior of YSZ and YSZ/NiCo coatings on inconel 625 exposed alkali chlorides

Alkali chloride attack on boiler pipe walls is considered the main problem of corrosion in the waste-to-energy (WTE) industry, even though uses superalloy. Electrophoretic deposited (EPD) yttria-stabilized zirconia (YSZ) coating is carried out to protect the Inconel 625 substrate. YSZ is deposited directly both on the Inconel 625 substrate and NiCo-Inconel 625. Corrosion resistance was conducted using the 3.5% NaCl electrochemical test and the hot salt corrosion test at 600°C in alkaline salt media such as NaCl, KCl, and CaCl2. The potentiodynamic polarization curve shows that the YSZ coating deposited on the substrate (single-layer) has a corrosion rate of 0.065 mm∙y‒1, lower than that deposited on NiCo coating (double-layer). The double-layer, NiO2 is formed in the NiCo layer due to the NaCl solution being trapped. Meanwhile, in hot salt corrosion at 600°C, CaCrO4 is formed as a protective oxide layer. Furthermore, in the double-layer, an imperfect oxide layer is formed causing spallation and coating failure. The corrosion rate for single-layer hot salt corrosion for 40 h is 0.310 mm∙y‒1. As a result, the corrosion resistance of the single-layer is increased by the presence of the Cr2O3 oxide layer formed during sintering.

Ultrafast Microwave-Assisted Synthesis of Porous NiCo Layered Double Hydroxide Nanospheres for High-Performance Supercapacitors.

Currently, new clean energy storage technology must be effective, affordable, and ecologically friendly so as to meet the diverse and sustainable needs of the energy supply. In this work, NiCo-LDH containing intercalated EG was successfully prepared within 210 s using an ultrafast microwave radiation technique. Subsequently, a series of characterization and systematic electrochemical tests were conducted to analyze the composition, structure, and energy storage mechanism of the NiCo-LDH material. The Ni:Co ratio of 5:5 results in the highest capacitance value of 2156 F/g at 1 A/g and an outstanding rate performance of 86.8% capacity retention rate at 10 A/g. The results demonstrated that the unique porous structure of NiCo-LDH and large layer spacing were conducive to more electrochemical reactions. Additionally, an electrochemical test was carried out on the NiCo-LDH as a hybrid supercapacitor electrode material, with NiCo-LDH-5:5 serving as the positive electrode and activated carbon as the negative electrode, the asymmetric supercapacitor can achieve a maximum energy density of 82.5 Wh kg-1 and power density of 8000 W kg-1. The NiCo-LDH-5:5//AC hybrid supercapacitors own 81.5% cycle stability and 100% coulombic efficiency after 6000 cycles at 10 A/g.

NiCo-LDH coupled with 2D ZIF-derived Co nitrogen doped carbon nanosheet arrays as a self-supporting electrocatalyst for detection of formaldehyde.

Formaldehyde is susceptible to illegal addition to foodstuffs to extend their shelf life due to its antimicrobial, preservative and bleaching properties. In this study, a self-supporting "nanosheet on nanosheet" arrays electrocatalyst with core-shell heterostructure was prepared in situ by coupling NiCo layer double hydroxide with 2D ZIF derived Co-nitrogen-doped porous carbon on carbon cloth (Co-N/C@NiCo-LDH NSAs/CC). Co-N/C nanosheet arrays act as a scaffold core with good electrical conductivity, providing more NiCo-LDH nucleation sites to avoid NiCo-LDH agglomeration, thus having fast mass/charge transfer performance. While the NiCo-LDH nanosheet arrays shell with high specific surface area provide more active sites for electrochemical reactions. As an electrocatalytic sensing electrode, Co-N/C@NiCo-LDH NSAs/CC has a wide linear range of 1 μM to 13 mM for formaldehyde detection, and the detection limit is 82 nM. Besides, the sensor has been applied to the detection of formaldehyde in food samples with satisfactory results.

The Interwoven Structured Two‐Dimensional NiCo Layered Double Hydroxide Tortuous Nanosheet as Performance‐Enhanced Electrode Material toward Battery‐Type Supercapacitor

The Interwoven Structured Two‐Dimensional NiCo Layered Double Hydroxide Tortuous Nanosheet as Performance‐Enhanced Electrode Material toward Battery‐Type Supercapacitor

Regulating the Oxygen Vacancy and Electronic Structure of NiCo Layered Double Hydroxides by Molybdenum Doping for High-Power Hybrid Supercapacitors.

Amelioration of nickel-cobalt layered double hydroxides (NiCo-LDH) with a high specific theoretical capacitance is of great desire for high-power supercapacitors. Herein, a molybdenum (Mo) doping strategy is proposed to improve the charge-storage performance of NiCo-LDH nanosheets growing on carbon cloth (CC) via a rapid microwave process. The regulation of the electronic structure and oxygen vacancy of the LDH is consolidated by the density functional theory (DFT) calculation, which demonstrates that Mo doping narrows the band gap, reduces the formation energy of hydroxyl vacancies, and promotes ionic and charge transfer as well as electrolyte adsorption on the electrode surface. The optimal Mo-doped NiCo-LDH electrode (MoNiCo-LDH-0.05/CC) has an amazing specific capacity of 471.1mA h g-1 at 1 A g-1 , and excellent capacity retention of 84.8% at 32 A g-1 , far superior to NiCo-LDH/CC (258.3mA h g-1 and 76.4%). The constructed hybrid supercapacitor delivers an energy density of 103.3W h kg-1 at a power density of 750W kg-1 and retains the cycle retention of 85.2% after 5000 cycles. Two assembled devices in series can drive thirty LED lamps, revealing a potential application prospect of the rationally synthesized MoNiCo-LDH/CC as an energy-storage electrode material.

Glucose pillared Ni-Co layered double hydroxide clay materials toward durable cathodes for alkaline zinc batteries

Alkaline Ni-Zn batteries are gaining more and more attention because of their safety, environmental friendliness, low cost and excellent performance. However, the volume and structure of the cathode changes during the charging and discharging process, resulting in particle flaking and structural rupture during the cyclic charging and discharging process, thus reducing their cyclic stability and limiting wide application. Herein, NiCo Layered double hydroxides (LDHs)clay materials with a low crystallinity multilayer nanosheet structure are prepared by glucose intercalation as cathode materials for alkaline Ni-Zn batteries. Expanded NiCo LDH layer spacing through glucose intercalation reduces interlayer peeling and collapse, accelerates interlayer diffusion of ions, and thus improves electron transport performance. NiCo LDH-G1.5 electrode material provides a specific capacity of 224 mAh g-1 and a capacity retention rate of 76% at a current density of 40 A g-1, 2000 cycles to maintain 86% of maximum capacity. Alkaline NiCo LDH-G1.5//Zn battery, a specific capacity of 180 mAh g-1 can be achieved at a high current density of 20 A g-1 and still maintain 76% of their maximum capacity after 2000 cycles, a maximum energy density of 364 Wh kg-1 and a maximum power density of 54 kW kg-1. This work provides a viable cathode for the development of high specific capacity and stable alkaline Ni-Zn batteries.

Fabrication of NiCo Layered Double Hydroxide on Carbon Fiber Paper as High Performance Binder-free Electrode for Supercapacitors

Design of binder-free electrode with high performance exhibits great glamour for energy storage devices recently. Herein, nickel cobalt layered double hydroxide (NiCo LDH) has been directly grown on carbon fiber paper (CFP) by an electrodeposition method. Thanks to the porous nanosheet-like morphology of the deposits, the high conductivity of carbon fibers, as well as the strong connection between the deposits and the substrate, the optimized electrode, labeled as NiCo LDH-2/CFP can deliver a discharge specific capacitance of 878.4 F g−1 at 1 A g−1, which can increase to 1080.0 F g−1 at 20 A g−1, exhibiting excellent rate performance. Moreover, after cycled at 5 A g−1 for 5000 cycles, the capacitance of the electrode can retain 96.1%, manifesting unique cyclic stability. This work provides a new strategy for preparing high performance binder-fee electrodes for supercapacitors, lithium batteries and catalytes.

Atomically Dispersed Silver Atoms Embedded in NiCo Layer Double Hydroxide Boost Oxygen Evolution Reaction.

Bimetallic layered double hydroxides (LDHs) are promising catalysts for anodic oxygen evolution reaction (OER) in alkaline media. Despite good stability, NiCo LDH displays an unsatisfactory OER activity relative to the most robust NiFe LDH and CoFe LDH. Herein, a novel NiCo LDH electrocatalyst modified with single-atom silver grown on carbon cloth (AgSA -NiCo LDH/CC) that exhibits exceptional OER activity and stability in 1.0m KOH is reported. The AgSA -NiCo LDH/CC catalyst only requires a low overpotential of 192mV to reach a current density of 10mA cm-2 , obviously boosting the OER activity of NiCo LDH/CC (410 mV@10mA cm-2 ). Inspiringly, AgSA -NiCo LDH/CC can maintain its high activity for up to 500h at a large current density of 100mA cm-2 , exceeding most single-atom OER catalysts. In situ Raman spectroscopy studies uncover that the in situ formed NiCoOOH during OER is the real active species. Hard X-ray absorption spectrum (XAS) and density functional theory (DFT) calculations validate that single-atom Ag occupying Ni site increases the chemical valence of Ni elements, and then weakens the adsorption of oxygen-contained intermediates on Ni sites, fundamentally accounting for the enhanced OER performance.

In Situ Growth of NiCo Layered Double Hydroxide on Biomass Waste‐Based Substrate: A Novel Material with 3D Interconnected Structure as Electrodes for Supercapacitors

Next‐generation energy storage systems require green and renewable electrodes with a high specific capacity, which combine biomass waste and bimetallic hydroxide synergically to satisfy environmental enhancements and economic benefits. Herein, a novel approach to improving the electrical conductivity of bimetallic materials by in situ growing NiCo layered double hydroxides (LDHs) with pseudocapacitance capability on KMnO4‐activated fungus bran‐derived carbons (FBCs) is reported, achieving improved electrochemical performance in supercapacitors (SCs). The hierarchical porous FBC substrate contributes to the homogeneous growth of the LDHs and high electronic and ionic conductivity. The optimal composite (FBC/NCL‐3) with a 3D interconnected structure provides a specific capacitance of 1938 F g−1 at a current density of 1 A g−1. Correspondingly, the hybrid battery‐SC device composed of FBC/NCL‐3 and FBC provides favorable stability (76% specific capacity retention at 5 A g−1 for 3000 cycles) with an operating voltage of 1.4 V and a high energy density of 37.3 Wh kg−1 at a power density of 695.6 W kg−1. This work demonstrates a promising strategy using FBC as a substrate for growing LDH materials aiming to achieve high‐performance SCs.

Electrochemical Sensor Based on Ni-Co Layered Double Hydroxide Hollow Nanostructures for Ultrasensitive Detection of Sumatriptan and Naproxen.

In this work, Ni-Co layered double hydroxide (Ni–Co LDH) hollow nanostructures were synthesized and characterized by X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), and Fourier-transform infrared spectroscopy (FT-IR) techniques. A screen-printed electrode (SPE) surface was modified with as-fabricated Ni–Co LDHs to achieve a new sensing platform for determination of sumatriptan. The electrochemical behavior of the Ni–Co LDH-modified SPE (Ni-CO LDH/SPE) for sumatriptan determination was investigated using voltammetric methods. Compared with bare SPE, the presence of Ni-Co LDH was effective in the enhancement of electron transport rate between the electrode and analyte, as well as in the significant reduction of the overpotential of sumatriptan oxidation. Differential pulse voltammetry (DPV) was applied to perform a quantitative analysis of sumatriptan. The linearity range was found to be between 0.01 and 435.0 μM. The limits of detection (LOD) and sensitivity were 0.002 ± 0.0001 μM and 0.1017 ± 0.0001 μA/μM, respectively. In addition, the performance of the Ni-CO LDH/SPE for the determination of sumatriptan in the presence of naproxen was studied. Simultaneous analysis of sumatriptan with naproxen showed well-separated peaks leading to a quick and selective analysis of sumatriptan. Furthermore, the practical applicability of the prepared Ni-CO LDH/SPE sensor was examined in pharmaceutical and biological samples with satisfactory recovery results.

Oxygen Vacancies Boosted by Laser Irradiation Enable NiCo Layered Double Hydroxide with a High Oxygen Reduction/Evolution Catalytic Activity in Zn–Air Batteries and Water Splitting

Oxygen Vacancies Boosted by Laser Irradiation Enable NiCo Layered Double Hydroxide with a High Oxygen Reduction/Evolution Catalytic Activity in Zn–Air Batteries and Water Splitting

Graphene frameworks-confined synthesis of 2D-layered NiCoP for the electrochemical sensing of H2O2 at lower overpotential.

A new 2D-layered nickel cobalt phosphide nanosheet confined by 3D graphene frameworks (denoted as NiCoP/GFs) is in situ controllably synthesized as a highlyefficient and durable electrocatalyst, which is obtained from the transformation of corresponding NiCo layer double hydroxides and GFs. Hydrogen peroxide (H2O2) is selected as a demonstration to study the electrochemical sensing performance of the NiCoP/GFs. Benefiting from 2D morphology of NiCoP and network structure of GFs, NiCoP/GFs exhibits remarkable electroactivity toward H2O2 at a relatively low overpotential of approximately - 0.3V (vs sat. Ag/AgCl)in 0.01M phosphate-buffered saline solution (PBS, pH = 7.4). The NiCoP/GFs-based H2O2 electrochemical sensor achieves a high sensitivity of ∼4398 μA mM-1cm-2, a low detection limit of 0.028 ± 0.006μM, and desirable selectivity. In addition, the sensor can sensitively detect H2O2 from living cancer cells. This study not merely broadens the synthesis methods of transition metal phosphide-based nanocrystals butthe NiCoP/GFs also has broad prospects in diverse electrochemistry fields. We have reported a controllable synthesis of 2D nickel cobalt phosphide nanosheet confined by graphene frameworks (denoted as NiCoP/GFs) as a greatly efficient and durable electrocatalyst. The NiCoP/GFs exhibits remarkable electroactivity toward detection of H2O2 at a relatively low overpotential of approximately-0.3 V. Density functional theory (DFT) calculations further prove that regulation of the electronic structure of NiCoP by GFs lowers the adsorption free energy of *OOH intermediates, and thus contributes to the greatly improved the electrocatalytic performance of NiCoP/GFs toward H2O2 reduction. The developed NiCoP/GFs can be applied as excellent electrode materials for efficient electrochemical sensing of H2O2.

Lightweight porous NiCo-SiC aerogel with synergistically dielectric and magnetic losses to enhance electromagnetic wave absorption performances

Microwave absorption performances can be remarkably enhanced using an electromagnetic (EM) wave absorber with synergistically dielectric and magnetic losses. In this study, the eggplant was used as a raw material to produce silicon carbide (SiC) aerogel by two steps: carbonization and subsequent carbothermic reduction. Then the magnetic NiCo layer was coated on the SiC aerogel (NiCo–SiC) by chemical plating method. The NiCo-SiC aerogel with an extremely low density (0.194 g/cm3) primarily composed of a porous SiC skeleton, SiC nanowires, and the magnetic NiCo alloy nanoparticles distributed on SiC skeleton and nanowires surfaces. The existence of magnetic NiCo alloy nanoparticles in the aerogel, the magnetic and dielectric losses are both increased by the formed heterogeneous interfaces. Thus, the NiCo–SiC aerogel with a thickness of 3 mm exhibits a minimum reflection loss (RLmin) of − 44.5 dB and an effective absorption bandwidth (RL<−10 dB) of 7.6 GHz, which displays the potential application in lightweight and excellent EM wave absorbers.

Pt Single Atom Captured by Oxygen Vacancy-Rich Nico Layered Double Hydroxides for Coupling Hydrogen Evolution with Selective Oxidation of Glycerol to Formate

Pt Single Atom Captured by Oxygen Vacancy-Rich Nico Layered Double Hydroxides for Coupling Hydrogen Evolution with Selective Oxidation of Glycerol to Formate

Fabrication of Nico Layered Double Hydroxide on Carbon Fiber Paper as High Performance Binder-Free Electrode for Supercapacitors

Fabrication of Nico Layered Double Hydroxide on Carbon Fiber Paper as High Performance Binder-Free Electrode for Supercapacitors

Core-Shell Composite of Cus Nanocages and Nico Layered Double Hydroxide Nanosheets with Modulated Electron Structure as “Two Birds with One Stone” Glucose Oxidation Electrocatalysts

Core-Shell Composite of Cus Nanocages and Nico Layered Double Hydroxide Nanosheets with Modulated Electron Structure as “Two Birds with One Stone” Glucose Oxidation Electrocatalysts

Synthesis of Cnt@Cos/Nico Layered Double Hydroxide with Hollow Nanocage to Enhance Supercapacitors Performance

Synthesis of Cnt@Cos/Nico Layered Double Hydroxide with Hollow Nanocage to Enhance Supercapacitors Performance

Electrically Enhanced Exchange Bias via Solid-State Magneto-ionics

Electrically induced ionic motion offers a new way to realize voltage-controlled magnetism, opening the door to a new generation of logic, sensor, and data storage technologies. Here, we demonstrate an effective approach to magneto-ionically and electrically tune the exchange bias in Gd/Ni1-xCoxO thin films (x = 0.50 and 0.67), where neither of the layers alone is ferromagnetic at room temperature. The Gd capping layer deposited onto antiferromagnetic Ni1-xCoxO initiates a solid-state redox reaction that reduces an interfacial region of the oxide to ferromagnetic NiCo. An exchange bias is established after field cooling (FC), which can be enhanced by up to 35% after a voltage conditioning and subsequently reset with a second FC. These effects are caused by the presence of an interfacial ferromagnetic NiCo layer, which further alloys with the Gd layer upon FC and voltage application, as confirmed by electron microscopy and polarized neutron reflectometry studies. These results highlight the viability of the solid-state magneto-ionic approach to achieve electric control of exchange bias, with potential for energy-efficient magneto-ionic devices.

NiCo layer double hydroxide/biomass-derived interconnected porous carbon for hybrid supercapacitors

Poplar catkins, as a typical biotemplate, has great potential for designing of interconnected porous carbon (IPC) toward hybrid supercapacitors. Herein, NiCo layered double hydroxide (LDH)/IPC composites were prepared and utilized as competitive materials of supercapacitor electrodes. NiCo LDH/IPC electrode displays the better electrochemical performance (209.7 mAh g − 1 at 1 A g − 1) than pure NiCo LDH electrode (148.6 mAh g − 1 at 1 A g − 1). Furthermore, the hybrid supercapacitors (HSCs) were assembled using a positive electrode of as-prepared NiCo LDH/IPC and a negative electrode of IPC. The NiCo LDH/IPC||IPC provides the higher specific energy of 29.6 Wh kg−1 and better cycling stability than NiCo LDH||IPC, which is ascribed to the introducing of IPC with advanced porous structure, improving the electrochemical performance.