Single Atom Ruthenium‐Doped CoP/CDs Nanosheets via Splicing of Carbon‐Dots for Robust Hydrogen Production

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(13), С. 7234 - 7244

Опубликована: Янв. 15, 2021

Abstract Ultrathin two‐dimensional catalysts are attracting attention in the field of electrocatalytic hydrogen evolution. This work describe a composite material design which CoP nanoparticles doped with Ru single‐atom sites supported on carbon dots (CDs) single‐layer nanosheets formed by splicing CDs (Ru 1 CoP/CDs). Small CD fragments bore abundant functional groups, analogous to pieces jigsaw puzzle, and could provide high density binding immobilize CoP. The single‐particle‐thick acted as supports, improved conductivity electrocatalyst stability catalyst during operation. CoP/CDs from doping atomic dispersed showed very efficiency for evolution reaction (HER) over wide pH range. prepared under optimized conditions displayed outstanding activity: overpotential HER at current 10 mA cm −2 was low 51 49 mV alkaline acidic conditions, respectively. Density theory calculations that substituted single atoms lowered proton‐coupled electron transfer energy barrier promoted H−H bond formation, thereby enhancing catalytic performance HER. findings open new avenue developing carbon‐based hybridization materials integrated water splitting.

Язык: Английский

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Self‐Supported Electrocatalysts for Practical Water Electrolysis

Advanced Energy Materials, Год журнала: 2021, Номер 11(39)

Опубликована: Сен. 1, 2021

Abstract Over the years, significant advances have been made to boost efficiency of water splitting by carefully designing economic electrocatalysts with augmented conductivity, more accessible active sites, and high intrinsic activity in laboratory test conditions. However, it remains a challenge develop earth‐abundant catalysts that can satisfy demands practical electrolysis, is, outstanding all‐pH electrolyte capacity, direct seawater ability, exceptional performance for overall splitting, superior large‐current‐density activity, robust long‐term durability. In this context, considering features increased species loading, rapid charge, mass transfer, strong affinity between catalytic components substrates, easily‐controlled wettability, as well as, enhanced bifunctional performance, self‐supported are presently projected be most suitable contenders massive scale hydrogen generation. review, comprehensive introduction design fabrication an emphasis on deposited nanostructured catalysts, selection various methods provided. Thereafter, recent development promising applications is reviewed from aforementioned aspects. Finally, brief conclusion delivered challenges perspectives relating promotion sustainable large‐scale production discussed.

Язык: Английский

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Vertically-interlaced NiFeP/MXene electrocatalyst with tunable electronic structure for high-efficiency oxygen evolution reaction

Science Bulletin, Год журнала: 2021, Номер 66(11), С. 1063 - 1072

Опубликована: Март 2, 2021

Язык: Английский

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Synergistic effect of multiple vacancies to induce lattice oxygen redox in NiFe-layered double hydroxide OER catalysts

Applied Catalysis B Environment and Energy, Год журнала: 2022, Номер 323, С. 122091 - 122091

Опубликована: Ноя. 3, 2022

Язык: Английский

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Unveiling Role of Sulfate Ion in Nickel‐Iron (oxy)Hydroxide with Enhanced Oxygen‐Evolving Performance

Advanced Functional Materials, Год журнала: 2021, Номер 31(38)

Опубликована: Июль 2, 2021

Abstract The rational design of effective catalysts for sluggish oxygen evolution reactions (OERs) is desired but challenging. Nickel‐iron (NiFe) (oxy)hydroxides are promising pre‐electrocatalysts alkaline OER. However, OER performances limited by the slow reconstruction process to generate active species high‐valance NiFe oxyhydroxides. In this work, a sulfate ion (SO 4 2− ) modulated strategy developed boost activity (oxy)hydroxide accelerating electrochemical pre‐catalyst and stabilizing reaction intermediate OOH* during SO decorated catalyst (NF‐S0.15) fabricated via scalable anodization foam in thiourea‐dissolved electrolyte. experimental theoretical investigations demonstrate dual effect on improving performances. leaching favorable form NiFeOOH under condition. Simultaneously, residual adsorbed surface can stabilize OOH*, thus enhance As expected, NF‐S0.15 delivers an ultralow overpotential 234 mV reach current density 50 mA cm −2 , fast kinetics (27.7 dec −1 ), high stability more than 100 h. This unique insights into anionic modification could inspire development advanced electrocatalysts efficient

Язык: Английский

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Constructing Built‐in Electric Field in Heterogeneous Nanowire Arrays for Efficient Overall Water Electrolysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(26)

Опубликована: Апрель 13, 2023

Efficient bifunctional electrocatalysts for hydrogen and oxygen evolution reactions are key to water electrolysis. Herein, we report a built-in electric field (BEF) strategy fabricate heterogeneous nickel phosphide-cobalt nanowire arrays grown on carbon fiber paper (Ni2 P-CoCH/CFP) with large work function difference (ΔΦ) as overall splitting. Impressively, Ni2 P-CoCH/CFP exhibits remarkable catalytic activity obtain 10 mA cm-2 , respectively. Moreover, the assembled lab-scale electrolyzer driven by an AAA battery delivers excellent stability after 50 h electrocatalysis 100 % faradic efficiency. Computational calculations combining experiments reveal interface-induced effect facilitates asymmetrical charge distributions, thereby regulating adsorption/desorption of intermediates during reactions. This offers avenue rationally design high-performance electrocatalysts.

Язык: Английский

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Co/CoP Heterojunction on Hierarchically Ordered Porous Carbon as a Highly Efficient Electrocatalyst for Hydrogen and Oxygen Evolution

Advanced Energy Materials, Год журнала: 2021, Номер 11(42)

Опубликована: Окт. 8, 2021

Abstract Designing non‐precious electrocatalysts to synergistically achieve a facilitated mass/electron transfer and exposure of abundant active sites is highly desired but remains significant challenge. Herein, composite electrocatalyst consisting dispersed Co/CoP heterojunction embedded within hierarchically ordered macroporous‐mesoporous‐microporous carbon matrix (Co/CoP@HOMC) rationally designed through the pyrolysis polystyrene sphere‐templated zeolite imidazolate framework‐67 (ZIF‐67) assemblies. The combined experimental theoretical calculations reveal that interfaces not only provide richly exposed also optimize hydrogen/water absorption free energy via electronic coupling, while interconnected macroporous structure enables superior mass all accessible sites. As result, as‐developed Co/CoP@HOMC composites exhibit outstanding catalytic activity with overpotentials 120 260 mV at 10 mA cm −2 for hydrogen evolution reaction oxygen in 1.0 m KOH, respectively. Moreover, an alkaline electrolyzer constructed by requires ultralow cell voltage 1.54 V , outperforming Pt@C||IrO 2 @C couple (1.64 V).

Язык: Английский

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S-doped nickel-iron hydroxides synthesized by room-temperature electrochemical activation for efficient oxygen evolution

Applied Catalysis B Environment and Energy, Год журнала: 2021, Номер 292, С. 120150 - 120150

Опубликована: Март 18, 2021

Язык: Английский

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Discovery of Quantitative Electronic Structure‐OER Activity Relationship in Metal‐Organic Framework Electrocatalysts Using an Integrated Theoretical‐Experimental Approach

Advanced Functional Materials, Год журнала: 2021, Номер 31(33)

Опубликована: Июнь 16, 2021

Abstract Developing cost‐effective and high‐performance catalysts for oxygen evolution reaction (OER) is essential to improve the efficiency of electrochemical conversion devices. Unfortunately, current studies greatly depend on empirical exploration ignore inherent relationship between electronic structure catalytic activity, which impedes rational design high‐efficiency OER catalysts. Herein, a series bimetallic Ni‐based metal‐organic frameworks (Ni‐M‐MOFs, M = Fe, Co, Cu, Mn, Zn) with well‐defined morphology active sites are selected as ideal platform explore electronic‐structure/catalytic‐activity relationship. By integrating density‐functional theory calculations experimental measurements, volcano‐shaped properties ( d ‐band center e g filling) activity demonstrated, in NiFe‐MOF optimized energy level situated closer volcano summit. It delivers ultra‐low overpotentials 215 297 mV 10 500 mA cm −2 , respectively. The identified electronic‐structure/catalytic found be universal other MOF (e.g., Ni‐M‐BDC‐NH 2 Ni‐M‐BTC, Ni‐M‐NDC, Ni‐M‐DOBDC, Ni‐M‐PYDC). This work widens applicability band filling descriptors prediction MOF‐based electrocatalysts, providing an insightful perspective highly efficient

Язык: Английский

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Reversed Active Sites Boost the Intrinsic Activity of Graphene‐like Cobalt Selenide for Hydrogen Evolution

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(22), С. 12360 - 12365

Опубликована: Март 16, 2021

Abstract Optimizing the hydrogen adsorption Gibbs free energy (Δ G H ) of active sites is essential to improve overpotential electrocatalytic evolution reaction (HER). We doped graphene‐like Co 0.85 Se with sulfur and found that are reversed (from cationic anionic S sites), which contributed an enhancement in HER performance. The optimal S‐doped composite has 108 mV (at 10 mA cm −2 a Tafel slope 59 dec −1 , exceeds other reported Se‐based electrocatalysts. have much higher activity than sites, close zero (0.067 eV), reduces barrier for production. This work provides inspiration optimizing intrinsic related transition metal chalcogenides.

Язык: Английский

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