Browse
Submit Data
Databases
API
Help

Dataset Information

32 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Regulating Water Reduction Kinetics on MoP Electrocatalysts Through Se Doping for Accelerated Alkaline Hydrogen Production

ABSTRACT: Owing to its low cost, high conductivity, and chemical stability, Molybdenum phosphide (MoP) has great potential for electrochemically catalyzing the hydrogen evolution reaction (HER). Unfortunately, the development of high-activity MoP still remains a grand challenge in alkali-electrolyzers due to its sluggish water reduction kinetics. Here, we demonstrate a novel strategy for regulating the HER kinetics of the MoP nanowire cathode through partially substituting P atoms with Se dopants. In alkaline solutions, the Se-doped MoP (Se-MoP) nanowire cathode exhibits excellent HER performance with a greatly-decreased overpotential of ∼61 mV at 10 mA cm−2 and a Tafel slope of ∼63 mV dec−1, outperforming currently reported MoP-based electrocatalysts. Experimental and theoretical investigations reveal that Se doping not only facilitates the water dissociation on MoP, but also optimize the hydrogen adsorption free energy, eventually speeding up the sluggish alkaline HER kinetics. Therefore, this work paves a new path for designing MoP-based electrocatalyst with high HER performance in alkaline electrolyzers.

SUBMITTER: Liu Z

PROVIDER: S-EPMC8517518 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Electrochemical Surface Restructuring of Phosphorus-Doped Carbon@MoP Electrocatalysts for Hydrogen Evolution.

Project description:The hydrogen evolution reaction (HER) through electrocatalysis is promising for the production of clean hydrogen fuel. However, designing the structure of catalysts, controlling their electronic properties, and manipulating their catalytic sites are a significant challenge in this field. Here, we propose an electrochemical surface restructuring strategy to design synergistically interactive phosphorus-doped carbon@MoP electrocatalysts for the HER. A simple electrochemical cycling method is developed to tune the thickness of the carbon layers that cover on MoP core, which significantly influences HER performance. Experimental investigations and theoretical calculations indicate that the inactive surface carbon layers can be removed through electrochemical cycling, leading to a close bond between the MoP and a few layers of coated graphene. The electrons donated by the MoP core enhance the adhesion and electronegativity of the carbon layers; the negatively charged carbon layers act as an active surface. The electrochemically induced optimization of the surface/interface electronic structures in the electrocatalysts significantly promotes the HER. Using this strategy endows the catalyst with excellent activity in terms of the HER in both acidic and alkaline environments (current density of 10 mA cm-2 at low overpotentials, of 68 mV in 0.5 M H2SO4 and 67 mV in 1.0 M KOH).

| S-EPMC8531175 | biostudies-literature

Facile Synthesis of MoP-RuP2 with Abundant Interfaces to Boost Hydrogen Evolution Reactions in Alkaline Media.

Project description:Exploiting efficient electrocatalysts for hydrogen evolution reactions (HERs) is important for boosting the large-scale applications of hydrogen energy. Herein, MoP-RuP2 encapsulated in N,P-codoped carbon (MoP-RuP2@NPC) with abundant interfaces were prepared via a facile avenue with the low-toxic melamine phosphate as the phosphorous resource. Moreover, the obtained electrocatalyst possessed a porous nanostructure, had abundant exposed active sites and improved the mass transport during the electrocatalytic process. Due to the above merits, the prepared MoP-RuP2@NPC delivered a greater electrocatalytic performance for HERs (50 mV@10 mA cm-2) relative to RuP2@NPC (120 mV) and MoP@NPC (195 mV) in 1 M KOH. Moreover, an ultralow potential of 1.6 V was required to deliver a current density of 10 mA cm-2 in the two-electrode configuration for overall water splitting. For practical applications, intermittent solar energy, wind energy and thermal energy were utilized to drive the electrolyzer to generate hydrogen gas. This work provides a novel and facile strategy for designing highly efficient and stable nanomaterials toward hydrogen production.

| S-EPMC8466548 | biostudies-literature

Nonprecious transition metal nitrides as efficient oxygen reduction electrocatalysts for alkaline fuel cells.

Project description:Hydrogen fuel cells have attracted growing attention for high-performance automotive power but are hindered by the scarcity of platinum (and other precious metals) used to catalyze the sluggish oxygen reduction reaction (ORR). We report on a family of nonprecious transition metal nitrides (TMNs) as ORR electrocatalysts in alkaline medium. The air-exposed nitrides spontaneously form a several-nanometer-thick oxide shell on the conductive nitride core, serving as a highly active catalyst architecture. The most active catalyst, carbon-supported cobalt nitride (Co3N/C), exhibited a half-wave potential of 0.862 V and achieved a record-high peak power density among reported nitride cathode catalysts of 700 mW cm-2 in alkaline membrane electrode assemblies. Operando x-ray absorption spectroscopy studies revealed that Co3N/C remains stable below 1.0 V but experiences irreversible oxidation at higher potentials. This work provides a comprehensive analysis of nonprecious TMNs as ORR electrocatalysts and will help inform future design of TMNs for alkaline fuel cells and other energy applications.

| S-EPMC8809680 | biostudies-literature

Single-atomic platinum on fullerene C60 surfaces for accelerated alkaline hydrogen evolution

Project description:The electrocatalytic hydrogen evolution reaction (HER) is one of the most studied and promising processes for hydrogen fuel generation. Single-atom catalysts have been shown to exhibit ultra-high HER catalytic activity, but the harsh preparation conditions and the low single-atom loading hinder their practical applications. Furthermore, promoting hydrogen evolution reaction kinetics, especially in alkaline electrolytes, remains as an important challenge. Herein, Pt/C60 catalysts with high-loading, high-dispersion single-atomic platinum anchored on C60 are achieved through a room-temperature synthetic strategy. Pt/C60-2 exhibits high HER catalytic performance with a low overpotential (η10) of 25 mV at 10 mA cm−2. Density functional theory calculations reveal that the Pt-C60 polymeric structures in Pt/C60-2 favors water adsorption, and the shell-like charge redistribution around the Pt-bonding region induced by the curved surfaces of two adjacent C60 facilitates the desorption of hydrogen, thus favoring fast reaction kinetics for hydrogen evolution. The synthesis of high-loading Pt single-atom catalysts is important but challenging. Here, the authors use fullerene C60 with electron-deficient C=C bonds to build Pt/C60 catalysts with abundant Pt single atoms which exhibits high catalytic activity for electrochemical hydrogen evolution reactions

| S-EPMC10147718 | biostudies-literature

Efficient hydrogen production on MoNi4 electrocatalysts with fast water dissociation kinetics.

Project description:Various platinum-free electrocatalysts have been explored for hydrogen evolution reaction in acidic solutions. However, in economical water-alkali electrolysers, sluggish water dissociation kinetics (Volmer step) on platinum-free electrocatalysts results in poor hydrogen-production activities. Here we report a MoNi4 electrocatalyst supported by MoO2 cuboids on nickel foam (MoNi4/MoO2@Ni), which is constructed by controlling the outward diffusion of nickel atoms on annealing precursor NiMoO4 cuboids on nickel foam. Experimental and theoretical results confirm that a rapid Tafel-step-decided hydrogen evolution proceeds on MoNi4 electrocatalyst. As a result, the MoNi4 electrocatalyst exhibits zero onset overpotential, an overpotential of 15 mV at 10 mA cm-2 and a low Tafel slope of 30 mV per decade in 1 M potassium hydroxide electrolyte, which are comparable to the results for platinum and superior to those for state-of-the-art platinum-free electrocatalysts. Benefiting from its scalable preparation and stability, the MoNi4 electrocatalyst is promising for practical water-alkali electrolysers.

| S-EPMC5442356 | 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

Ruthenium-cobalt nanoalloys encapsulated in nitrogen-doped graphene as active electrocatalysts for producing hydrogen in alkaline media.

Project description:The scalable production of hydrogen could conveniently be realized by alkaline water electrolysis. Currently, the major challenge confronting hydrogen evolution reaction (HER) is lacking inexpensive alternatives to platinum-based electrocatalysts. Here we report a high-efficient and stable electrocatalyst composed of ruthenium and cobalt bimetallic nanoalloy encapsulated in nitrogen-doped graphene layers. The catalysts display remarkable performance with low overpotentials of only 28 and 218 mV at 10 and 100 mA cm-2, respectively, and excellent stability of 10,000 cycles. Ruthenium is the cheapest platinum-group metal and its amount in the catalyst is only 3.58 wt.%, showing the catalyst high activity at a very competitive price. Density functional theory calculations reveal that the introduction of ruthenium atoms into cobalt core can improve the efficiency of electron transfer from alloy core to graphene shell, beneficial for enhancing carbon-hydrogen bond, thereby lowing ΔGH* of HER.

| S-EPMC5413983 | biostudies-literature

Ru catalyst supported on nitrogen-doped nanotubes as high efficiency electrocatalysts for hydrogen evolution in alkaline media.

Project description:Due to the potential application in the future energy conversion system, there is an increasing demand for efficient, stable and cheap platinum-free catalysts for hydrogen evolution. However, it is still a great challenge to develop electrocatalysts with high activity similar to platinum or even higher, especially those that can work under alkaline conditions. Ruthenium (Ru), as a cheap substitute for platinum, has been studied as a feasible substitute for (HER) catalyst for hydrogen evolution reaction. In this paper, we designed and developed a novel Ru catalyst (Ru@CNT) supported on nitrogen-doped carbon nanotubes. Electrochemical tests show that even under alkaline conditions (1 M KOH), Ru@CNT still shows excellent catalytic performance and good durability. It only needs 36.69 mV overpotential to reach a current density of 10 mA cm-2, and its Tafel slope is 28.82 mV dec-1. The catalytic performance of the catalyst is comparable to that of 20% Pt/C. The significant activity is mainly attributed to the chelation of highly dispersed ruthenium atoms on nitrogen-doped carbon nanotubes. Secondly, the one-dimensional pore structures supported by nitrogen heterocarbon nanotubes can provide more opportunities for active centers. Excellent HER performance makes Ru@CNT electrocatalyst have a broad application prospect in practical hydrogen production.

| S-EPMC9054606 | biostudies-literature

Electronic modulation of transition metal phosphide via doping as efficient and pH-universal electrocatalysts for hydrogen evolution reaction.

Project description:It is highly desirable to develop efficient and low-cost catalysts to minimize the overpotential of the hydrogen evolution reaction (HER) for large-scale hydrogen production from electrochemical water splitting. Doping a foreign element into the host catalysts has been proposed as an effective approach to optimize the electronic characteristics of catalysts and thus improve their electrocatalytic performance. Herein we, for the first time, report vanadium-doped CoP on self-supported conductive carbon cloth (V-CoP/CC) as a robust HER electrocatalyst, which achieves ultra-low overpotentials of 71, 123 and 47 mV to afford a current density of 10 mA cm-2 in 1 M KOH, 1 M PBS and 0.5 M H2SO4 media, respectively. Meanwhile, the V-CoP/CC electrode exhibits a small Tafel slope and superior long-term stability over a wide pH range. Detailed characterizations reveal that the modulation of the electronic structure contributes to the superior HER performance of V-CoP/CC. We believe that doping engineering opens up new opportunities to improve the HER catalytic activity of transition metal phosphides through regulating their physicochemical and electrochemical properties.

| S-EPMC5892309 | biostudies-literature

Octahedral spinel electrocatalysts for alkaline fuel cells.

Project description:Designing high-performance nonprecious electrocatalysts to replace Pt for the oxygen reduction reaction (ORR) has been a key challenge for advancing fuel cell technologies. Here, we report a systematic study of 15 different AB2O4/C spinel nanoparticles with well-controlled octahedral morphology. The 3 most active ORR electrocatalysts were MnCo2O4/C, CoMn2O4/C, and CoFe2O4/C. CoMn2O4/C exhibited a half-wave potential of 0.89 V in 1 M KOH, equal to the benchmark activity of Pt/C, which was ascribed to charge transfer between Co and Mn, as evidenced by X-ray absorption spectroscopy. Scanning transmission electron microscopy (STEM) provided atomic-scale, spatially resolved images, and high-energy-resolution electron-loss near-edge structure (ELNES) enabled fingerprinting the local chemical environment around the active sites. The most active MnCo2O4/C was shown to have a unique Co-Mn core-shell structure. ELNES spectra indicate that the Co in the core is predominantly Co2.7+ while in the shell, it is mainly Co2+ Broader Mn ELNES spectra indicate less-ordered nearest oxygen neighbors. Co in the shell occupies mainly tetrahedral sites, which are likely candidates as the active sites for the ORR. Such microscopic-level investigation probes the heterogeneous electronic structure at the single-nanoparticle level, and may provide a more rational basis for the design of electrocatalysts for alkaline fuel cells.

| S-EPMC6900538 | 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