Browse
Submit Data
Databases
API
Help

Dataset Information

30 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Electrodeposition of amorphous molybdenum sulfide thin film for electrochemical hydrogen evolution reaction.

ABSTRACT: Amorphous molybdenum sulfide (MoS_x) is a highly active noble-metal-free electrocatalysts for the hydrogen evolution reaction (HER). The MoS_x was prepared by electrochemical deposition at room temperature. Low-cost precursors of Mo and S were adopted to synthesize thiomolybdates solution as the electrolyte. It replaces the expensive (NH)₂MoS₄ and avoid the poison gas (H₂S) to generate or employ. The (MoO₂S₂)^2-, (MoOS₃)^2- and (MoS₄)^2- ions were determined by UV-VIS spectroscopy. The electrodeposition of MoS_x was confirmed with XRD, XPS and SEM. The electrocatalyst activity was measured by polarization curve. The electrolyte contained (MoO₂S₂)^2- ion and (MoOS₃)^2- ion electrodeposit the MoS_x thin film displays a relatively high activity for HER with low overpotential of 211 mV at a current density of 10 mA cm^-2, a relatively high current density of 21.03 mA cm^-2 at η = 250 mV, a small Tafel slope of 55 mV dec^-1. The added sodium dodecyl sulfate (SDS) can efficient improve the stability of the MoS_x film catalyst.

SUBMITTER: Zhang L

PROVIDER: S-EPMC6661953 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Efficient All-2D Amorphous Cobalt Sulfide Nanosheets/Multilayered Molybdenum Disulfide Hybrid Heterojunction Catalyst for Electrochemical Hydrogen Evolution.

Project description:Hydrogen energy is considered to be a critical environmentally friendly and widely sourced renewable energy source that can be used as an alternative to fossil fuels. At present, the preparation of hydrogen (H2) mainly depends on traditional fossil fuels. In order to achieve sustainable development of environmental protection, great attention has been paid to the preparation of H2 by electrocatalysis, photocatalysis, and photoelectrochemistry. Here, it is reported for the first time that a novel active catalyst for the hydrogen evolution reaction, consisting of all-2D amorphous nanosheets/2D crystal layer heterojunction structure and without any noble metal (no precious metals are present in the preparation or measuring), is almost entirely fabricated by laser ablation in liquid (LAL) growth of amorphous cobalt sulfide on the surface of multilayered molybdenum disulfide. In acidic media, the amorphous cobalt sulfide nanosheets/multilayered molybdenum disulfide (a-CoS/MoS2) catalyst exhibits fast hydrogen evolution kinetics with onset potential of -147 mV and a Tafel slope of 126 mV per decade, which is much better than only the amorphous cobalt sulfide and molybdenum disulfide layer. The high hydrogen evolution activity of the amorphous cobalt sulfide nanosheets/multilayered molybdenum disulfide hybrid is likely due to the unique electrocatalytic synergistic effects between hydrogen evolution-active amorphous cobalt sulfide nanosheets and layered crystal molybdenum disulfide materials, as well as the much-increased catalytic sites. This work provides a new general route based on all-2D amorphous nanosheets/2D crystal structure for designing and preparing novel layered materials with effectively manipulated catalytic properties and active functionality surface.

| S-EPMC7001116 | biostudies-literature

Coordination polymer structure and revisited hydrogen evolution catalytic mechanism for amorphous molybdenum sulfide.

Project description:Molybdenum sulfides are very attractive noble-metal-free electrocatalysts for the hydrogen evolution reaction (HER) from water. The atomic structure and identity of the catalytically active sites have been well established for crystalline molybdenum disulfide (c-MoS2) but not for amorphous molybdenum sulfide (a-MoSx), which exhibits significantly higher HER activity compared to its crystalline counterpart. Here we show that HER-active a-MoSx, prepared either as nanoparticles or as films, is a molecular-based coordination polymer consisting of discrete [Mo3S13](2-) building blocks. Of the three terminal disulfide (S2(2-)) ligands within these clusters, two are shared to form the polymer chain. The third one remains free and generates molybdenum hydride moieties as the active site under H2 evolution conditions. Such a molecular structure therefore provides a basis for revisiting the mechanism of a-MoSx catalytic activity, as well as explaining some of its special properties such as reductive activation and corrosion. Our findings open up new avenues for the rational optimization of this HER electrocatalyst as an alternative to platinum.

| S-EPMC5495159 | biostudies-literature

Tuning the Composition and Structure of Amorphous Molybdenum Sulfide/Carbon Black Nanocomposites by Radiation Technique for Highly Efficient Hydrogen Evolution.

Project description:Amorphous molybdenum sulfide/carbon black (MoSx/C) nanocomposites are synthesized by a facile one-step ?-ray radiation induced reduction process. Amorphous MoSx shows better intrinsic activity than crystalline MoS2. And the composition and amorphous structure of MoSx could be expediently tuned by absorbed dose for excellent catalytic activity. Meanwhile, the addition of carbon black leads to a significant decrease of charge transfer resistance and increase of active sites of MoSx/C composite. Consequently, MoSx/C nanocomposite shows Pt-like catalytic activity towards hydrogen evolution reaction (HER), which requires an onset over potential of 40?mV and over potential of 76?mV to achieve a current density of 10?mA?cm-2, and the corresponding Tafel slope is 48?mV decade-1. After 6000 CV cycles, the catalytic activity of MoSx/C shows no obvious decrease. However, when platinum (Pt) foil is used as counter electrode, MoSx/C composite show better catalytic activity abnormally after long-term cycling tests. The dissolution of Pt was observed in HER and the Pt dissolution mechanism is elucidated by further analyzing the surface composition of after-cycling electrodes, which offers highly valuable guidelines for using Pt electrode in HER.

| S-EPMC5700052 | biostudies-literature

Recent advances in unveiling active sites in molybdenum sulfide-based electrocatalysts for the hydrogen evolution reaction.

Project description:Hydrogen has received significant attention as a promising future energy carrier due to its high energy density and environmentally friendly nature. In particular, the electrocatalytic generation of hydrogen fuel is highly desirable to replace current fossil fuel-dependent hydrogen production methods. However, to achieve widespread implementation of electrocatalytic hydrogen production technology, the development of highly active and durable electrocatalysts based on Earth-abundant elements is of prime importance. In this context, nanostructured molybdenum sulfides (MoS x ) have received a great deal of attention as promising alternatives to precious metal-based catalysts. In this focus review, we summarize recent efforts towards identification of the active sites in MoS x -based electrocatalysts for the hydrogen evolution reaction (HER). We also discuss recent synthetic strategies for the engineering of catalyst structures to achieve high active site densities. Finally, we suggest ongoing and future research challenges in the design of advanced MoS x -based HER electrocatalysts.

| S-EPMC5524877 | biostudies-other

Porous Cobalt Sulfide Selenium Nanorods for Electrochemical Hydrogen Evolution.

Project description:A key process in electrochemical energy technology is hydrogen evolution reaction (HER). However, its electrochemical properties mainly depend on the catalytic activity of the material itself. Therefore, it is important to find efficient electrocatalysts to realize clean hydrogen production. As a typical kind of catalytic materials, transition metal dichalcogenides (TMCs) play important roles in the field of energy catalysis. As a representative of TMCs, cobalt disulfide (CoS2), recently has raised much research interest owing to its abundant reserves, environmental friendliness, and excellent electrochemical stability. Meanwhile, given the fact that doping is one of the effective methods to improve the electrochemical catalytic property, various means of doping have been researched. Here, we report for the first time that porous-like Se-CoS2-x (or Se:CoS2-x ) nanorod can be facilely synthesized via a controllable two-step strategy. It is demonstrated that doping Se can greatly improve the catalytic performance of CoS2 electrode. The electrode can obtain a current density of 10 mA cm-2 at overpotential of only ∼260 mV. And the current changes with the applied bias voltage in an obvious stepped pattern, in the chronopotential (CP) curve of Se-CoS2-x , indicating its outstanding mass transfer property and mechanical stability.

| S-EPMC8444292 | biostudies-literature

Pt nanoparticles-decorated molybdenum nitrides for efficient hydrogen evolution reaction.

Project description:Exploring low cost and high efficiency catalysts for hydrogen production from electrochemical water splitting is preferable and remains a significant challenge. As an alternative to Pt-based catalysts, molybdenum nitrides have attracted more attention for their hydrogen evolution reaction (HER). However, their performance is restricted due to the strong bonding of Mo-H. Herein, molybdenum nitrides with Pt-doping are fabricated to enhance the catalytic activity for HER in acidic solution. As expected, Pt (5 wt%)-MoNx delivers a low overpotential of 47 mV at a current density of 10 mA cm-2 with a high exchange current density (j0 = 0.98 mA cm-2). The superior performance is attributed to the modified electronic structure of Mo with Pt incorporation.

| S-EPMC10662210 | biostudies-literature

Interfacial electronic structure engineering on molybdenum sulfide for robust dual-pH hydrogen evolution.

Project description:Molybdenum disulfide, as an electronic highly-adjustable catalysts material, tuning its electronic structure is crucial to enhance its intrinsic hydrogen evolution reaction (HER) activity. Nevertheless, there are yet huge challenges to the understanding and regulation of the surface electronic structure of molybdenum disulfide-based catalysts. Here we address these challenges by tuning its electronic structure of phase modulation synergistic with interfacial chemistry and defects from phosphorus or sulfur implantation, and we then successfully design and synthesize electrocatalysts with the multi-heterojunction interfaces (e.g., 1T0.81-MoS2@Ni2P), demonstrating superior HER activities and good stabilities with a small overpotentials of 38.9 and 95 mV at 10 mA/cm2, a low Tafel slopes of 41 and 42 mV/dec in acidic as well as alkaline surroundings, outperforming commercial Pt/C catalyst and other reported Mo-based catalysts. Theoretical calculation verified that the incorporation of metallic-phase and intrinsic HER-active Ni-based materials into molybdenum disulfide could effectively regulate its electronic structure for making the bandgap narrower. Additionally, X-ray absorption spectroscopy indicate that reduced nickel possesses empty orbitals, which is helpful for additional H binding ability. All these factors can decrease Mo-H bond strength, greatly improving the HER catalytic activity of these materials.

| S-EPMC8421379 | biostudies-literature

Direct In Situ Growth of Centimeter-Scale Multi-Heterojunction MoS2/WS2/WSe2 Thin-Film Catalyst for Photo-Electrochemical Hydrogen Evolution.

Project description:To date, the in situ fabrication of the large-scale van der Waals multi-heterojunction transition metal dichalcogenides (multi-TMDs) is significantly challenging using conventional deposition methods. In this study, vertically stacked centimeter-scale multi-TMD (MoS2/WS2/WSe2 and MoS2/WSe2) thin films are successfully fabricated via sequential pulsed laser deposition (PLD), which is an in situ growth process. The fabricated MoS2/WS2/WSe2 thin film on p-type silicon (p-Si) substrate is designed to form multistaggered gaps (type-II band structure) with p-Si, and this film exhibits excellent spatial and thickness uniformity, which is verified by Raman spectroscopy. Among various application fields, MoS2/WS2/WSe2 is applied to the thin-film catalyst of a p-Si photocathode, to effectively transfer the photogenerated electrons from p-Si to the electrolyte in the photo-electrochemical (PEC) hydrogen evolution. From a comparison between the PEC performances of the homostructure TMDs (homo-TMDs)/p-Si and multi-TMDs/p-Si, it is demonstrated that the multistaggered gap of multi-TMDs/p-Si improves the PEC performance significantly more than the homo-TMDs/p-Si and bare p-Si by effective charge transfer. The new in situ growth process for the fabrication of multi-TMD thin films offers a novel and innovative method for the application of multi-TMD thin films to various fields.

| S-EPMC6662091 | biostudies-literature

Ultra-Thin SnS2-Pt Nanocatalyst for Efficient Hydrogen Evolution Reaction.

Project description:Transition-metal dichalcogenides (TMDs) materials have attracted much attention for hydrogen evolution reaction (HER) as a new catalyst, but they still have challenges in poor stability and high reaction over-potential. In this study, ultra-thin SnS2 nanocatalysts were synthesized by simple hydrothermal method, and low load of Pt was added to form stable SnS2-Pt-3 (the content of platinum is 0.5 wt %). The synergistic effect between ultra-thin SnS2 rich in active sites and individual dispersed Pt nanoclusters can significantly reduce the reaction barrier and further accelerate HER reaction kinetics. Hence, SnS2-Pt-3 exhibits a low overpotential of 210 mV at the current density of 10 mA cm-2. It is worth noting that SnS2-Pt-3 has a small Tafel slope (126 mV dec-1) in 0.5 M H2SO4, as well as stability. This work provides a new option for the application of TMDs materials in efficient hydrogen evolution reaction. Moreover, this method can be easily extended to other catalysts with desired two-dimensional materials.

| S-EPMC7760803 | biostudies-literature

Electrocatalytic Hydrogen Evolution from a Cobaloxime-Based Metal-Organic Framework Thin Film.

Project description:Molecular hydrogen evolution catalysts (HECs) are synthetically tunable and often exhibit high activity, but they are also hampered by stability concerns and practical limitations associated with their use in the homogeneous phase. Their incorporation as integral linker units in metal-organic frameworks (MOFs) can remedy these shortcomings. Moreover, the extended three-dimensional structure of MOFs gives rise to high catalyst loadings per geometric surface area. Herein, we report a new MOF that exclusively consists of cobaloximes, a widely studied HEC, that act as metallo-linkers between hexanuclear zirconium clusters. When grown on conducting substrates and under applied reductive potential, the cobaloxime linkers promote electron transport through the film as well as function as molecular HECs. The obtained turnover numbers are orders of magnitude higher than those of any other comparable cobaloxime system, and the molecular integrity of the cobaloxime catalysts is maintained for at least 18 h of electrocatalysis. Being one of the very few hydrogen evolving electrocatalytic MOFs based on a redox-active metallo-linker, this work explores uncharted terrain for greater catalyst diversity and charge transport pathways.

| S-EPMC6803166 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data