Browse
Submit Data
Databases
API
Help

Dataset Information

22 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Supra Hydrolytic Catalysis of Ni₃ Fe/rGO for Hydrogen Generation.

ABSTRACT: Light metal hydrolysis for hydrogen supply is well suited for portable hydrogen fuel cells. The addition of catalysts can substantially aid Mg hydrolysis. However, there is a lack of clear catalytic mechanism to guide the design of efficient catalysts. In this work, the essential role of nanosized catalyst (Ni₃ Fe/rGO) in activating micro-sized Mg with ultra-rapid hydrolysis process is investigated for the first time. Here, an unprecedented content of 0.2 wt% Ni₃ Fe/rGO added Mg can release 812.4 mL g^-1 hydrogen in just 60 s at 30 °C. Notably, an impressive performance with a hydrogen yield of 826.4 mL g^-1 at 0 °C in only 30 s is achieved by the Mg-2 wt% Ni₃ Fe/rGO, extending the temperature range for practical applications of hydrolysis. Moreover, the four catalysts (Ni₃ Fe/rGO, Ni₃ Fe, Ni/rGO, Fe/rGO) are designed to reveal the influence of composition, particle size, and dispersion on catalytic behavior. Theoretical studies corroborate that the addition of Ni₃ Fe/rGO accelerates the electron transfer and coupling processes and further provides a lower energy barrier diffusion path for hydrogen. Thus, a mechanism concerning the catalyst as migration relay is proposed. This work offers guidelines designing high-performance catalysts especially for activating the hydrolysis of micro-sized light weight metals.

SUBMITTER: Liu J

PROVIDER: S-EPMC9313488 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Synthesis of Ni4.5Fe4.5S8/Ni3S2 film on Ni3Fe alloy foam as an excellent electrocatalyst for the oxygen evolution reaction.

Project description:Directly synthesizing bicomponent electrocatalysts in the nanostructured form from bulk alloy foam has many potential advantages: robust stability, synergistic effects and fast electron transfer. Here, Ni4.5Fe4.5S8/Ni3S2 film with micrometer thickness on bulk substrate was synthesized by a simple one-step hydrothermally assisted sulfurization of Ni3Fe alloy foam for the oxygen evolution reaction (OER) in basic media. Benefiting from the synergetic effect of the bicomponent, reduced interfacial resistance between electrocatalyst and metal substrate, and more exposed catalytic sites on the microstructured film, the as-prepared electrocatalyst (Ni4.5Fe4.5S8/Ni3S2‖Ni3Fe) behaves as a highly efficient and robust oxygen evolution electrode with felicitous current density in alkaline electrolytes (1 M KOH). It requires an overpotential of only 264 mV to drive 100 mA cm-2 with its catalytic activity being maintained for at least 20 h in 1 M KOH. In the near future, this kind of synthesis strategy can be easily extended to investigate many electrocatalysts derived from 3D alloyed foam with various ratios of the different components, opening new avenue for understanding the relationship between material properties and electrochemical performance.

| S-EPMC9062387 | biostudies-literature

Zn0.8Cd0.2S Hollow Spheres with a Highly Dispersed Ni Dopant for Boosting Photocatalytic Hydrogen Generation.

Project description:Facilitating charge separation and increasing surface active sites have always been the goals of photocatalysis. Herein, we synthesized a Ni-doped Zn0.8Cd0.2S hollow sphere photocatalyst with a facile one-step hydrothermal method. Energy-dispersive spectroscopy mapping showed the high dispersion of Ni ions in the Zn0.8Cd0.2S hollow spheres. The experimental results confirmed that Ni doping reduced the band structure of the substrate, suppressed the recombination of photo-induced electrons and holes, and provided more reactive sites. Therefore, the photocatalytic activity had been greatly improved. As a consequence, the detected photocatalytic H2 evolution rate increased up to 33.81 mmol·h-1·g-1 over an optimal Ni doping (5 wt %) of Zn0.8Cd0.2S hollow spheres, which was 20.87-fold higher than that of pure CdS. Elemental mapping showed that the Zn element was mainly distributed in the outermost layer of the hollow spheres; this might be the critical factor that enabled Ni-doped Zn x Cd1-x S to maintain excellent stability.

| S-EPMC8173556 | biostudies-literature

Renewable Hydrogen and Electricity Dispatch with Multiple Ni-Fe Electrode Storage.

Project description: Not available

| S-EPMC6373986 | biostudies-literature

High-capacity and high-rate Ni-Fe batteries based on mesostructured quaternary carbon/Fe/FeO/Fe3O4 hybrid material.

Project description:The Ni-Fe battery is a promising alternative to lithium ion batteries due to its long life, high reliability, and eco-friendly characteristics. However, passivation and self-discharge of the iron anode are the two main issues. Here, we demonstrate that controlling the valence state of the iron and coupling with carbon can solve these problems. We develop a mesostructured carbon/Fe/FeO/Fe3O4 hybrid by a one-step solid-state reaction. Experimental evidence reveals that the optimized system with three valence states of iron facilitates the redox kinetics, while the carbon layers can effectively enhance the charge transfer and suppress self-discharge. The hybrid anode exhibits high specific capacity of 604 mAh⋅g-1 at 1 A⋅g-1 and high cyclic stability. A Ni-Fe button battery is fabricated using the hybrid anode exhibits specific device energy of 127 Wh⋅kg-1 at a power density of 0.58 kW⋅kg-1 and maintains good capacity retention (90%) and coulombic efficiency (98.5%).

| S-EPMC8184513 | biostudies-literature

Lightweight Chain-Typed Magnetic Fe3O4@rGO Composites with Enhanced Microwave-Absorption Properties.

Project description:A lightweight microwave-absorbing material with a strong electromagnetic-absorption capability of practical significance in the field of electromagnetic compatibility was obtained by adjusting the ratio of Fe3O4 and rGO. A nanoparticle material with a chain-typed structure consisting of a combination of Fe3O4 and rGO was produced by a hydrothermal method under an applied magnetic field. The electromagnetic loss property of the Fe3O4@rGO composites is studied in the frequency range from 2 to 18 GHz. In addition, the reflection loss and the mechanism of microwave absorption are explored. By changing the amounts of rGO, the electromagnetic loss of the Fe3O4@rGO composites can be effectively regulated, which obtain better reflection loss. The minimum reflection loss of the Fe3O4@rGO composites is -49.4 dB at 16.2 GHz only with a thickness of 1.75 mm. Thus, the Fe3O4@rGO composites have an extremely thin thickness and a strong electromagnetic wave absorption capacity, which is a candidate for the development of lightweight magnetic absorbing materials.

| S-EPMC9612295 | biostudies-literature

Direct measurement of Ni incorporation into Fe3O4(001).

Project description:The normal incidence X-ray standing wave (NIXSW) technique has been used to follow the evolution of the adsorption geometry of Ni adatoms on the Fe3O4(001)-(?2 × ?2)R45° surface as a function of temperature. Two primary surface region sites are identified: a bulk-continuation tetrahedral site and a sub-surface octahedral site, the latter site being preferred at higher annealing temperatures. The ease of incorporation is linked to the presence of subsurface cation vacancies in the (?2 × ?2)R45° reconstruction and is consistent with the preference for octahedral coordination observed in the spinel compound NiFe2O4.

| S-EPMC6011209 | biostudies-literature

Accelerated alkaline hydrogen evolution on M(OH) x /M-MoPO x (M = Ni, Co, Fe, Mn) electrocatalysts by coupling water dissociation and hydrogen ad-desorption steps.

Project description:Developing efficient and cheap electrocatalysts for the alkaline hydrogen evolution reaction is still a big challenge due to the sluggish water dissociation kinetics as well as poor M-Had energetics. Herein, hydroxide modification and element incorporation have been demonstrated to realize a synergistic modulation on a new class of M(OH) x /M-MoPO x catalysts for accelerating water dissociation and hydrogen ad-desorption steps in the HER. Theoretical and experimental results disclosed that in situ modification with hydroxide endowed M(OH) x /M-MoPO x with a strong ability to dissociate water, and meanwhile, oxygen incorporation effectively optimized the M-Had energetics of the NiMoP catalyst. Moreover, the interaction between M(OH) x and M-MoPO x components in M(OH) x /M-MoPO x further enhances their ability to catalyze the two elementary steps in alkaline hydrogen evolution, providing a wide avenue for efficiently catalyzing hydrogen evolution. In general, the optimized Ni(OH)2/NiMoPO x catalyst exhibits excellent alkaline HER activity and durability, superior to the state-of-the-art Pt/C catalyst when the overpotential exceeds 65 mV.

| S-EPMC8157449 | biostudies-literature

Advanced Ultrathin RuPdM (M = Ni, Co, Fe) Nanosheets Electrocatalyst Boosts Hydrogen Evolution.

Project description:The hydrogen evolution reaction (HER) is one of the most significant reactions in the electrolysis water process, and electrocatalysts which possess high mass activity and excellent stability are the most important driving factors to improve the efficiency of HER. As for the efficient commercially electrocatalyst, Pt/C is limited in development because of its high cost. Therefore, the study of non-Pt high-efficiency catalysts is particularly important at this moment. Here, we creatively report for the first time a kind of RuPdM (M= Ni, Co, Fe) ultrathin nanosheets (NSs), which exhibit extraordinary electrochemical properties for HER under alkaline conditions. The overpotential of optimized trimetallic Ru38Pd34Ni28 ultrathin NSs is only 20 mV (10 mA cm-2), and the mass activity reaches 6.15 A mg-1 noble metal at -0.07 V vs RHE. It can be compared to Pt-based electrocatalysts, which have the highest mass activity currently reported. The durability tests also prove that the stability of the electrocatalyst is outstanding. DFT calculations disclose that the flexible modulation of electronic structures of RuPd ultrathin NSs is achieved by utilizing the additional 3d transition metals Fe, Co, and Ni. In particular, the Ni-3d bands act as the continuous electron-supply center for Ru to ensure an efficient electron transfer toward the adsorbates. Meanwhile, the stable Pd sites are critical for coupling the O-2p? orbital in the initial H2O splitting with a facile barrier. This work will open up a new era of non-Pt materials for alkaline hydrogen evolution toward practical application.

| S-EPMC6936089 | biostudies-literature

(Fe0.2Ni0.8)0.96S tubular spheres supported on Ni foam as an efficient bifunctional electrocatalyst for overall water splitting.

Project description:Earth-abundant and efficient bifunctional electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are highly significant for renewable energy systems. However, the performance of existing electrocatalysts is usually restricted by the low electroic conductivity and the limited amount of exposed active sites. In this work, (Fe0.2Ni0.8)0.96S tubular spheres supported on Ni foam have been prepared by a sulfuration of FeNi layered double hydroxide spheres grown on Ni foam. Benefiting from the unique tubular sphere architecture, the rich inner defects and the enhanced electron interactions between Fe, Ni and S, this electrocatalyst shows low overpotential of 48?mV for HER at 10?mA cm-2 in 1.0?mol L-1 KOH solution, which is one of the lowest value of non-previous electrocatalyts for HER in alkaline electrolyte. Furthermore, assembled this versatile electrode as an alkaline electrolyzer for overall water splitting, a current density of 10?mA cm-2 is achieved at a low cell voltage of 1.56?V, and reach up to 30?mA cm-2 only at an operating cell voltage of 1.65?V.

| S-EPMC6013453 | biostudies-literature

3D β-Ni(OH)2 nanowires/RGO composite prepared by phase transformation method for superior electrochemical performance.

Project description:In order to improve the capacity and rate performance of nickel-metal hydride (Ni-MH) batteries, we proposed a simple phase transformation method to synthesis 3D β-nickel hydroxide nanowires/reduced graphene oxide (β-Ni(OH)2 NWs/RGO) composite. β-Ni(OH)2 nanowires with diameters of 20-30 nm and lengths up to several micrometers were decorated on RGO layers, forming 3D network structure. The 3D β-Ni(OH)2 NWs/RGO composite displayed a discharge capacity of 343.2 mAh/g at 0.2C, and the capacity values has almost no loss after 100th cycles. When the discharge rate was at 5C, the capacity reached a value of 272.7 mAh/g, and its capacity retention was 79.5%. It showed good capacity and rate performance as a positive material for Ni-MH batteries.

| S-EPMC6658499 | biostudies-literature