Stabilizing Low‐Valence Single Atoms by Constructing Metalloid Tungsten Carbide Supports for Efficient Hydrogen Oxidation and Evolution

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(42)

Published: Sept. 2, 2023

Abstract Designing novel single‐atom catalysts (SACs) supports to modulate the electronic structure is crucial optimize catalytic activity, but rather challenging. Herein, a general strategy proposed utilize metalloid properties of trap and stabilize single‐atoms with low‐valence states. A series supported on surface tungsten carbide (M‐WC x , M=Ru, Ir, Pd) are rationally developed through facile pyrolysis method. Benefiting from WC exhibit weak coordination W C atoms, resulting in formation active centers similar metals. The unique metal‐metal interaction effectively stabilizes single atoms improves orbital energy level distribution sites. As expected, representative Ru‐WC exhibits superior mass activities 7.84 62.52 mg Ru −1 for hydrogen oxidation evolution reactions (HOR/HER), respectively. In‐depth mechanistic analysis demonstrates that an ideal dual‐sites cooperative mechanism achieves suitable adsorption balance H ad OH energetically favorable Volmer step. This work offers new guidance precise construction highly SACs.

Language: Английский

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Symmetry‐Broken Ru Nanoparticles with Parasitic Ru‐Co Dual‐Single Atoms Overcome the Volmer Step of Alkaline Hydrogen Oxidation

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(12)

Published: Jan. 30, 2024

Abstract Efficient dual‐single‐atom catalysts are crucial for enhancing atomic efficiency and promoting the commercialization of fuel cells, but addressing sluggish kinetics hydrogen oxidation reaction (HOR) in alkaline media facile site generation remains formidable challenges. Here, we break local symmetry ultra‐small ruthenium (Ru) nanoparticles by embedding cobalt (Co) single atoms, which results release Ru atoms from on reduced graphene oxide (Co 1 1,n /rGO). In situ operando spectroscopy theoretical calculations reveal that oxygen‐affine Co atom disrupts nanoparticles, resulting parasitic within nanoparticles. The interaction between forms effective active centers. parasitism modulates adsorption OH intermediates sites, accelerating HOR through faster formation *H 2 O. As anticipated, /rGO exhibits ultrahigh mass activity (7.68 A mg −1 ) at 50 mV exchange current density (0.68 mA cm −2 ), 6 7 times higher than those Ru/rGO, respectively. Notably, it also displays exceptional durability surpassing commercial Pt catalysts. This investigation provides valuable insights into hybrid multi‐single‐atom metal nanoparticle catalysis.

Language: Английский

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Ultrathin Rh Nanosheets with Rich Grain Boundaries for Efficient Hydrogen Oxidation Electrocatalysis

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(49), P. 27010 - 27021

Published: Nov. 10, 2023

Two-dimensional (2D) Pt-group ultrathin nanosheets (NSs) are promising advanced electrocatalysts for energy-related catalytic reactions. However, improving the electrocatalytic activity of 2D NSs through addition abundant grain boundaries (GBs) and understanding underlying formation mechanism remain significant challenges. Herein, we report controllable synthesis a series Rh-based nanocrystals (e.g., Rh nanoparticles, NSs, with GBs) CO-mediated kinetic control route. In light NSs' structural advantages GB modification, rich GBs exhibit an enhanced compared to pure commercial Pt/C toward hydrogen oxidation reaction (HOR) in alkaline media. Both experimental results theoretical computations corroborate that have capacity ameliorate adsorption free energy intermediates during HOR, thus resulting outstanding HOR performance. Our work offers novel perspectives realm developing sophisticated metal conversion field.

Language: Английский

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Highly Crystalline Iridium–Nickel Nanocages with Subnanopores for Acidic Bifunctional Water Splitting Electrolysis

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(11), P. 7858 - 7867

Published: March 8, 2024

Developing efficient bifunctional materials is highly desirable for overall proton membrane water splitting. However, the design of iridium with high acidic splitting activity and durability, as well an in-depth understanding catalytic mechanism, challenging. Herein, we successfully developed subnanoporous Ir3Ni ultrathin nanocages crystallinity The shell enables NCs optimized exposure active sites. Importantly, nickel incorporation contributes to favorable thermodynamics electrocatalysis OER after surface reconstruction hydrogen adsorption free energy in HER electrocatalysis, which induce enhanced intrinsic oxygen evolution reaction (OER) (HER). Together, achieve 3.72 A/mgIr(η=350 mV) 4.47 A/mgIr(η=40 mass activity, are 18.8 times 3.3 higher than that commercial IrO2 Pt, respectively. In addition, their crystalline identity ensures a robust nanostructure, enabling good durability during oxidation. This work provides new revenue toward structural insightful metal alloy mechanisms electrocatalysis.

Language: Английский

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Efficient and durable seawater electrolysis with a V ₂ O ₃ -protected catalyst

Science Advances, Journal Year: 2024, Volume and Issue: 10(20)

Published: May 17, 2024

The ocean, a vast hydrogen reservoir, holds potential for sustainable energy and water development. Developing high-performance electrocatalysts production under harsh seawater conditions is challenging. Here, we propose incorporating protective V 2 O 3 layer to modulate the microcatalytic environment create in situ dual-active sites consisting of low-loaded Pt Ni N. This catalyst demonstrates an ultralow overpotential 80 mV at 500 mA cm −2 , mass activity 30.86 times higher than Pt-C maintains least hours seawater. Moreover, assembled anion exchange membrane electrolyzers (AEMWE) demonstrate superior durability even demanding industrial conditions. In localized pH analysis elucidates environmental regulation mechanism layer. Its role as Lewis acid enables sequestration excess OH − ions, mitigate Cl corrosion, alkaline earth salt precipitation. Our protection strategy by using presents promising cost-effective approach large-scale green production.

Language: Английский

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Hydrogen oxidation electrocatalysts for anion-exchange membrane fuel cells: activity descriptors, stability regulation, and perspectives

Energy & Environmental Science, Journal Year: 2024, Volume and Issue: 17(12), P. 3960 - 4009

Published: Jan. 1, 2024

The general principles in terms of reactivity and stability to design efficient electrocatalysts for the alkaline hydrogen oxidation reaction are reviewed. performance catalysts anion-exchange membrane fuel cells is further discussed.

Language: Английский

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Atomically dispersed Iridium on Mo2C as an efficient and stable alkaline hydrogen oxidation reaction catalyst

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: May 18, 2024

Abstract Hydroxide exchange membrane fuel cells (HEMFCs) have the advantages of using cost-effective materials, but hindered by sluggish anodic hydrogen oxidation reaction (HOR) kinetics. Here, we report an atomically dispersed Ir on Mo 2 C nanoparticles supported carbon (Ir SA -Mo C/C) as highly active and stable HOR catalysts. The specific current density C/C is 4.1 mA cm −2 ECSA , which 10 times that Ir/C. Negligible decay observed after 30,000-cycle accelerated stability test. Theoretical calculations suggest high activity attributed to unique substrate, makes sites with optimized H binding also provides enhanced OH sites. By a low loading (0.05 mg ) anode, fabricated HEMFC can deliver peak power 1.64 W . This work illustrates precious metal carbides may be promising strategy for performance HEMFCs.

Language: Английский

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Sub‐2 nm Microstrained High‐Entropy‐Alloy Nanoparticles Boost Hydrogen Electrocatalysis

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(32)

Published: May 25, 2024

Abstract High‐entropy alloys (HEAs) confine multifarious elements into the same lattice, leading to intense lattice distortion effect. The tends induce local microstrain at atomic level and thus affect surface adsorptions toward different adsorbates in various electrocatalytic reactions, yet remains unexplored. Herein, this work reports a class of sub‐2 nm IrRuRhMoW HEA nanoparticles (NPs) with distinct induced by for boosting alkaline hydrogen oxidation (HOR) evolution reactions (HER). This demonstrates that distortion‐rich catalysts optimized electronic structure can downshift d‐band center generate uncoordinated oxygen sites enhance oxophilicity. As result, NPs show remarkable HOR kinetic current density 8.09 mA µg −1 PGM 50 mV versus RHE, 8.89, 22.47 times higher than those IrRuRh without internal strain commercial Pt/C, respectively, which is best value among all reported non‐Pt based catalysts. also display great HER performances turnover frequency (TOF) 5.93 H 2 s 70 4.6‐fold Pt/C catalyst, exceeding most noble metal‐based Experimental characterizations theoretical studies collectively confirm weakened (H ad ) enhanced hydroxyl (OH adsorption are achieved simultaneously modulating binding energy oxophilicity originated from intensified ligand effect over NPs, guarantees HOR/HER.

Language: Английский

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Dilute RuCo Alloy Synergizing Single Ru and Co Atoms as Efficient and CO‐Resistant Anode Catalyst for Anion Exchange Membrane Fuel Cells

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(28)

Published: April 26, 2024

Abstract Ruthenium (Ru) is considered a promising candidate catalyst for alkaline hydroxide oxidation reaction (HOR) due to its hydrogen binding energy (HBE) like that of platinum (Pt) and much higher oxygenophilicity than Pt. However, Ru still suffers from insufficient intrinsic activity CO resistance, which hinders widespread use in anion exchange membrane fuel cells (AEMFCs). Here, we report hybrid (RuCo) NC+SAs /N‐CNT consisting dilute RuCo alloy nanoparticles atomically single Co atoms on N‐doped carbon nanotubes The exhibits state‐of‐the‐art with high mass 7.35 A mg −1 . More importantly, when used as an anode AEMFCs, peak power density reaches 1.98 W cm −2 , one the best AEMFCs properties noble metal‐based catalysts at present. Moreover, has superior long‐time stability resistance. experimental functional theory (DFT) results demonstrate alloying monodecentralization exotic element greatly modulates electronic structure host Ru, thus optimizing adsorption H OH promoting surface, then stimulates HOR tolerance catalyst.

Language: Английский

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All-round enhancement induced by oxophilic single Ru and W atoms for alkaline hydrogen oxidation of tiny Pt nanoparticles

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 21, 2025

Anion exchange membrane fuel cells (AEMFCs) are one of the ideal energy conversion devices. However, platinum (Pt), as benchmark catalyst for hydrogen oxidation reaction (HOR) AEMFCs anodes, still faces issues insufficient performance and susceptibility to CO poisoning. Here, we report Joule heating-assisted synthesis a small sized Ru1Pt single-atom alloy loaded on nitrogen-doped carbon modified with single W atoms (s-Ru1Pt@W1/NC), in which near-range Ru nanoparticles long-range support simultaneously modulate electronic structure active Pt-site, enhancing alkaline HOR s-Ru1Pt@W1/NC. The mass activity s-Ru1Pt@W1/NC is 7.54 A mgPt+Ru-1 exhibits notable stability 1000 ppm CO/H2-saturated electrolyte. Surprisingly, it can operate stably H2-saturated electrolyte h only 24.60 % decay. Theoretical calculations demonstrate that proximal remote synergistically optimize improving tolerance catalyst. development anode catalysts anion-exchange promising but challenging practical applications. authors tiny catalyze very high activity, stability, resistance.

Language: Английский

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