Electrocatalysts for Zinc–Air Batteries Featuring Single Molybdenum Atoms in a Nitrogen‐Doped Carbon Framework

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(35)

Published: June 16, 2023

Bifunctional catalysts can facilitate two different electrochemical reactions with conflicting characteristics. Here, a highly reversible bifunctional electrocatalyst for rechargeable zinc-air batteries (ZABs) is reported featuring "core-shell structure" in which N-doped graphene sheets wrap around vanadium molybdenum oxynitride nanoparticles. Single Mo atoms are released from the particle core during synthesis and anchored to electronegative N-dopant species graphitic shell. The resultant single-atom excel as active oxygen evolution reaction (OER) sites pyrrolic-N reduction (ORR) pyridinic-N environments. ZABs such multicomponent deliver high power density (≈376.4 mW cm-2 ) long cycle life of over 630 h, outperforming noble-metal-based benchmarks. Flexible that tolerate wide range temperatures (-20 80 °C) under severe mechanical deformation also demonstrated.

Language: Английский

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Integration of Alloy Segregation and Surface CoO Hybridization in Carbon‐Encapsulated CoNiPt Alloy Catalyst for Superior Alkaline Hydrogen Evolution

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(41)

Published: July 28, 2023

Abstract Constructing an efficient alkaline hydrogen evolution reaction (HER) catalyst with low platinum (Pt) consumption is crucial for the cost reduction of energy devices, such as electrolyzers. Herein, nanoflower‐like carbon‐encapsulated CoNiPt alloy catalysts composition segregation are designed by pyrolyzing morphology‐controlled and Pt‐proportion‐tuned metal–organic frameworks (MOFs). The optimized containing 15% NFs (15%: Pt mass percentage, NFs: nanoflowers) exhibits outstanding HER performance a overpotential 25 mV at current density 10 mA cm −2 , far outperforming those commercial Pt/C (47 mV) most advanced catalysts. Such superior activity originates from integration Co‐O hybridization. hierarchical structure guarantees full exposure sites. Density functional theory calculations suggest that components not only promote water dissociation but also facilitate adsorption process, synergistically accelerating kinetics HER. In addition, volcanically distributed surface oxygen content, mainly in form Co 3d O 2p hybridization, which another reason enhanced activity. This work provides feasible insights into design cost‐effective coordinating kinetic sites adjusting appropriate content.

Language: Английский

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Encapsulating Cobalt Nanoparticles in Interconnected N‐Doped Hollow Carbon Nanofibers with Enriched CoNC Moiety for Enhanced Oxygen Electrocatalysis in Zn‐Air Batteries

Advanced Science, Journal Year: 2021, Volume and Issue: 8(20)

Published: Aug. 16, 2021

Rational design of bifunctional efficient electrocatalysts for both oxygen reduction (ORR) and evolution reactions (OER) is desirable-while highly challenging-for development rechargeable metal-air batteries. Herein, an electrocatalyst designed fabricated by encapsulating Co nanoparticles in interconnected N-doped hollow porous carbon nanofibers (designated as Co@N-C/PCNF) using ultrafast high-temperature shock technology. Benefiting from the synergistic effect intrinsic activity CoNC moiety, well structure nanofibers, Co@N-C/PCNF composite shows high electrocatalytic activities OER (289 mV at 10 mA cm-2 ) ORR (half-wave potential 0.85 V). The moiety can modulate local environmental electrical catalysts, thus optimizing adsorption/desorption kinetics decreasing reaction barriers promoting reversible electrocatalysis. Co@N-C/PCNF-based aqueous Zn-air batteries (AZAB) provide power density 292 mW , assembled flexible ZAB wearable devices.

Language: Английский

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1D/3D Heterogeneous Assembling Body as Trifunctional Electrocatalysts Enabling Zinc–Air Battery and Self‐Powered Overall Water Splitting

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 32(4)

Published: Oct. 10, 2021

Abstract Developing low‐cost, efficient, and stable trifunctional electrocatalyst for oxygen reduction reaction (ORR), evolution (OER), hydrogen (HER) is still a significant challenge. Herein, this study reports zeolitic imidazolate framework (ZIF) derived electrocatalyst, composed of Co 5.47 N 7 Fe 3 (CoFeN) that embedded into 1D N‐doped carbon nanotubes modified 3D cruciform matrix (NCNTs//CCM). Benefiting from the robust interfacial conjugation N/Co 1D/3D hierarchical structure with large surface area, as‐prepared CoFeN‐NCNTs//CCM display electrocatalytic activity ORR (half‐wave potential 0.84 V), OER (320 mV at 10 mA cm –2 ), HER (−151 ). The assembled Zn‐air battery exhibits high power density (145 mW ) , enhanced charge–discharge performance (voltage gap 0.76 V long‐term cycling stability (over 445 h). resultant overall water‐splitting cell achieves current 1.63 V, which can compete best reported catalysts. What more, self‐assembled batteries are utilized to water splitting successfully, verifying great as functional material sustainable energy storage conversion system.

Language: Английский

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FeCo/FeCoP encapsulated in N, Mn-codoped three-dimensional fluffy porous carbon nanostructures as highly efficient bifunctional electrocatalyst with multi-components synergistic catalysis for ultra-stable rechargeable Zn-air batteries

Journal of Colloid and Interface Science, Journal Year: 2021, Volume and Issue: 605, P. 451 - 462

Published: July 23, 2021

Language: Английский

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N, S Codoped Carbon Matrix‐Encapsulated Co₉S₈ Nanoparticles as a Highly Efficient and Durable Bifunctional Oxygen Redox Electrocatalyst for Rechargeable Zn–Air Batteries

Advanced Energy Materials, Journal Year: 2021, Volume and Issue: 11(28)

Published: June 10, 2021

Abstract Herein, a N, S co‐doped carbon encapsulating Co 9 8 nanoparticles (Co @N, S–C) catalyst is successfully synthesized by new precursor of Co‐pyridine coordinated‐polymer consisting 2,6‐diacetylpyridine and 4,4′‐dithiodianiline. Benefiting from the abundant pore‐structure (average pore‐size ≈25nm) unique electronic‐properties S–C layer, as‐prepared S‐C exhibits rapid oxygen reduction reaction (ORR) kinetics with high electron transfer number ≈3.998 demonstrates low overpotential 304 mV for evolution (OER). It small potential difference 0.647V overall ORR/OER activity, outperforming most non‐precious metal‐catalysts previously reported. The rechargeable Zn–Air battery test further its excellent activity stability, in which delivers maximum power density output 259 mW cm −2 , specific capacity 862 mAh g Zn −1 after continuous 110 h operation charge‐discharge round‐trip efficiency only reduces 4.83%. Theoretical calculation studies show that surface layers can adjust each other's Fermi levels, so adsorption energy on O intermediate more favorable than using alone. This study reveals structure‐function relationship coated‐nanostructures multifunctional electrocatalytic properties, provides feasible strategy design non‐noble metal‐catalysts.

Language: Английский

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Carbon-based bifunctional electrocatalysts for oxygen reduction and oxygen evolution reactions: Optimization strategies and mechanistic analysis

Journal of Energy Chemistry, Journal Year: 2022, Volume and Issue: 71, P. 234 - 265

Published: March 25, 2022

Language: Английский

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Metal-organic framework-derived transition metal chalcogenides (S, Se, and Te): Challenges, recent progress, and future directions in electrochemical energy storage and conversion systems

Coordination Chemistry Reviews, Journal Year: 2023, Volume and Issue: 480, P. 215030 - 215030

Published: Jan. 23, 2023

Language: Английский

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Recent advances and challenges of metal–organic framework/graphene-based composites

Composites Part B Engineering, Journal Year: 2021, Volume and Issue: 230, P. 109532 - 109532

Published: Nov. 30, 2021

Language: Английский

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In situ produced Co9S8 nanoclusters/Co/Mn-S, N multi-doped 3D porous carbon derived from eriochrome black T as an effective bifunctional oxygen electrocatalyst for rechargeable Zn-air batteries

Journal of Colloid and Interface Science, Journal Year: 2021, Volume and Issue: 608, P. 2100 - 2110

Published: Oct. 29, 2021

Language: Английский

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