Heterostructures Composed of N‐Doped Carbon Nanotubes Encapsulating Cobalt and β‐Mo₂C Nanoparticles as Bifunctional Electrodes for Water Splitting

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(15), P. 4923 - 4928

Published: Jan. 12, 2019

Herein, we demonstrate the use of heterostructures comprised Co/β-Mo2 C@N-CNT hybrids for hydrogen evolution reaction (HER) and oxygen (OER) in an alkaline electrolyte. The Co can not only create a well-defined heterointerface with β-Mo2 C but also overcomes poor OER activity C, thus leading to enhanced electrocatalytic HER OER. DFT calculations further proved that cooperation between N-CNTs, Co, results lower energy barriers intermediates greatly enhances performance. This study provides simple strategy construction nonprecious metals, in-depth insight into mechanism solution.

Language: Английский

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Single Atoms and Clusters Based Nanomaterials for Hydrogen Evolution, Oxygen Evolution Reactions, and Full Water Splitting

Advanced Energy Materials, Journal Year: 2019, Volume and Issue: 9(22)

Published: May 2, 2019

Abstract The sustainable and scalable production of hydrogen through evolution reaction (HER) oxygen (OER) in water splitting demands efficient robust electrocatalysts. Currently, state‐of‐the‐art electrocatalysts Pt IrO 2 /RuO exhibit the benchmark catalytic activity toward HER OER, respectively. However, expanding their practical application is hindered by exorbitant price scarcity. Therefore, development alternative effective for crucial. In last few decades, substantial effort has been devoted to HER/OER catalysts based on various transition metals (including Fe, Co, Ni, Mo, atomic Pt) which show promising activities durability. this review, after a brief introduction basic mechanism HER/OER, authors systematically discuss recent progress design, synthesis, single atom cluster‐based catalysts. Moreover, crucial factors that can tune such as morphology, crystal defects, hybridization with nonmetals, heteroatom doping, alloying, formation inside graphitic layered materials are discussed. Finally, existing challenges future perspectives improving performance addressed.

Language: Английский

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Structural Design and Electronic Modulation of Transition‐Metal‐Carbide Electrocatalysts toward Efficient Hydrogen Evolution

Advanced Materials, Journal Year: 2018, Volume and Issue: 31(2)

Published: Aug. 21, 2018

As the key of hydrogen economy, electrocatalytic evolution reactions (HERs) depend on availability cost-efficient electrocatalysts. Over past years, there is a rapid rise in noble-metal-free Among them, transition metal carbides (TMCs) are highlighted due to their structural and electronic merits, e.g., high conductivity, metallic band states, tunable surface/bulk architectures, etc. Herein, representative efforts progress made TMCs comprehensively reviewed, focusing noble-metal-like configuration relevant structural/electronic modulation. Briefly, specific nanostructures carbon-based hybrids introduced increase active-site abundance promote mass transportation, heteroatom doping heterointerface engineering encouraged optimize chemical configurations active sites toward intrinsically boosted HER kinetics. Finally, perspective future development TMC electrocatalysts offered. The overall aim shed some light exploration emerging materials energy chemistry.

Language: Английский

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Recent Advances and Prospective in Ruthenium-Based Materials for Electrochemical Water Splitting

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(11), P. 9973 - 10011

Published: Sept. 25, 2019

As a highly appealing technology for hydrogen generation, water electrolysis including oxygen evolution reaction (OER) at the anode and (HER) cathode largely depends on availability of efficient electrocatalysts. Accordingly, over past years, much effort has been made to develop various electrocatalysts with superior performance reduced cost. Among them, ruthenium (Ru)-based materials OER HER are very promising because their prominent catalytic activity, pH-universal application, cheapest price among precious metal family, so on. Herein, recent advances in this hot research field comprehensively reviewed. A general description about splitting is presented understand mechanism proposed scaling relations toward activities, key stability issues Ru-based further given. Subsequently, Ru-involving introduced classified into different groups improving or optimizing electrocatalytic properties, special focus several significant bifunctional along simulated electrolyzer. Finally, perspective existing challenges future progress catalysts provided. The main aim here shed some light design construction emerging energy storage conversion technologies.

Language: Английский

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Ultrafine Co Nanoparticles Encapsulated in Carbon‐Nanotubes‐Grafted Graphene Sheets as Advanced Electrocatalysts for the Hydrogen Evolution Reaction

Advanced Materials, Journal Year: 2018, Volume and Issue: 30(30)

Published: June 10, 2018

The rational design of an efficient and inexpensive electrocatalyst based on earth-abundant 3d transition metals (TMs) for the hydrogen evolution reaction still remains a significant challenge in renewable energy area. Herein, novel effective approach is developed synthesizing ultrafine Co nanoparticles encapsulated nitrogen-doped carbon nanotubes (N-CNTs) grafted onto both sides reduced graphene oxide (rGO) (Co@N-CNTs@rGO) by direct annealing GO-wrapped core-shell bimetallic zeolite imidazolate frameworks. Benefiting from uniform distribution nanoparticles, in-situ-formed highly graphitic N-CNTs@rGO, large surface area, abundant porosity, as-fabricated Co@N-CNTs@rGO composites exhibit excellent electrocatalytic (HER) activity. As demonstrated electrochemical measurements, can achieve 10 mA cm-2 at low overpotential with only 108 87 mV 1 m KOH 0.5 H2 SO4 , respectively, much better than most reported Co-based electrocatalysts over wide pH range. More importantly, synthetic strategy versatile be extended to prepare other binary or even ternary TMs@N-CNTs@rGO (e.g., Co-Fe@N-CNTs@rGO Co-Ni-Cu@N-CNTs@rGO). here may open new avenue toward development nonprecious high-performance HER catalysts.

Language: Английский

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Enhanced Catalysis of Electrochemical Overall Water Splitting in Alkaline Media by Fe Doping in Ni₃S₂ Nanosheet Arrays

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(6), P. 5431 - 5441

Published: May 3, 2018

The development of bifunctional electrocatalysts with high performance for both hydrogen evolution reaction (HER) and oxygen (OER) earth-abundant elements is still a challenge in electrochemical water splitting technology. Herein, we fabricated free-standing electrocatalyst the form vertically oriented Fe-doped Ni3S2 nanosheet array grown on three-dimensional (3D) Ni foam (Fe-Ni3S2/NF), which presented activity durability HER OER alkaline media. On basis systematic experiments calculation, Fe-doping was evidenced to increase surface area, improve adsorption ability, optimize energy Ni3S2, resulted enhancement Fe-Ni3S2/NF. Moreover, metal sites Fe-Ni3S2/NF were proved play significant role process. During catalysis OER, formation Ni–Fe (oxy)hydroxide observed near-surface section Fe-Ni3S2/NF, introduction Fe element dramatically enhanced Ni3S2. overall electrolyzer assembled by exhibited low cell voltage (1.54 V @ 10 mA cm–2) 1 M KOH. This work demonstrated promising electrolysis media potential application future.

Language: Английский

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Direct observation of active catalyst surface phases and the effect of dynamic self-optimization in NiFe-layered double hydroxides for alkaline water splitting

Energy & Environmental Science, Journal Year: 2019, Volume and Issue: 12(2), P. 572 - 581

Published: Jan. 1, 2019

Identification of active catalyst surface phases and the influence dynamic self-optimization in NiFe-layered double hydroxides for alkaline water splitting.

Language: Английский

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MOF‐Derived Bifunctional Cu₃P Nanoparticles Coated by a N,P‐Codoped Carbon Shell for Hydrogen Evolution and Oxygen Reduction

Advanced Materials, Journal Year: 2017, Volume and Issue: 30(6)

Published: Dec. 21, 2017

Metal-organic frameworks (MOFs) have recently emerged as a type of uniformly and periodically atom-distributed precursor efficient self-sacrificial template to fabricate hierarchical porous-carbon-related nanostructured functional materials. For the first time, Cu-based MOF, i.e., Cu-NPMOF is used, whose linkers contain nitrogen phosphorus heteroatoms, single prepare novel Cu3 P nanoparticles (NPs) coated by N,P-codoped carbon shell that extended porous matrix with identical uniform N doping (termed P@NPPC) an electrocatalyst. P@NPPC demonstrates outstanding activity for both hydrogen evolution oxygen reduction reaction, representing example P-based bifunctional catalyst energy-conversion reactions. The high performances are ascribed specific surface area, synergistic effects NPs intrinsic activity, protection shell, doped multiheteroatoms. This strategy using diverse MOF structural compositional material create new multifunctional composite/hybrid may expand opportunities explore highly robust non-noble-metal catalysts

Language: Английский

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MXene: an emerging two-dimensional material for future energy conversion and storage applications

Journal of Materials Chemistry A, Journal Year: 2017, Volume and Issue: 5(47), P. 24564 - 24579

Published: Jan. 1, 2017

The development of two-dimensional (2D) high-performance electrode materials is the key to new advances in fields energy conversion and storage. MXenes, a intriguing family 2D transition metal carbides, nitrides, carbonitrides, have recently received considerable attention due their unique combination properties such as high electrical conductivity, hydrophilic nature, excellent thermal stability, large interlayer spacing, easily tunable structure, surface area. In this review, we discuss how MXenes emerged efficient economical nanomaterials for future applications. We highlight promising potential these storage applications, water electrolyzers, lithium ion batteries, supercapacitors. Finally, present an outlook sustainable technologies.

Language: Английский

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Metal oxide-based materials as an emerging family of hydrogen evolution electrocatalysts

Energy & Environmental Science, Journal Year: 2020, Volume and Issue: 13(10), P. 3361 - 3392

Published: Jan. 1, 2020

Metal oxide-based materials are emerging as a promising family of hydrogen evolution reaction (HER) electrocatalysts.

Language: Английский

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