Electronic Structure Regulation of MnCo₂O₄ via Surface‐Phosphorization Coupling to Monolithic Carbon for Oxygen Electrocatalysis in Zn–Air Batteries

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: July 1, 2024

Abstract An urgent challenge to the development of rechargeable Zn–air batteries (RZABs) is highly active, durable, and low‐cost catalysts for oxygen reduction reaction evolution (ORR OER). Herein, a carbon‐based monolithic catalyst designed via anchoring P‐modified MnCo 2 O 4 inverse spinel nanoparticles on biomass‐derived carbon (P‐MnCo @PWC). The introduction surface P atoms regulates electronic structures valences metal by adjusting coordination fields (P‐O) δ– Metal‐P. optimization adsorption behavior key intermediates facilitates activation conversion species. structure beneficial construction three‐phase interface efficient mass transfer high electrical conductivity. P‐MnCo @PWC displays outstanding bifunctional catalytic properties with thin Δ E (the difference between OER potential at 10 mA cm – ORR halfwave potential) 0.66 V. RZAB as cathode delivers an exceptional peak power density (160 mW ) remarkable cycle life (over 1200 cycles), overcoming those noble counterparts. This research provides promising general surface‐phosphorization way design electrocatalysts high‐value utilization biomass.

Language: Английский

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High‐Density Accessible Iron Single‐Atom Catalyst for Durable and Temperature‐Adaptive Laminated Zinc‐Air Batteries

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 7, 2025

Abstract Designing single‐atom catalysts (SACs) with high density of accessible sites by improving metal loading and utilization is a promising strategy to boost the catalytic activity, but remains challenging. Herein, site (SD) iron SAC (D‐Fe‐N/C) 11.8 wt.% Fe‐loading reported. The in situ scanning electrochemical microscopy technique attests that active SD D‐Fe‐N/C reach as 1.01 × 10 21 g −1 79.8%, respectively. Therefore, demonstrates superior oxygen reduction reaction (ORR) activity terms half‐wave potential 0.918 V turnover frequency 0.41 e s . excellent ORR property also demonstrated liquid zinc‐air batteries (ZABs), which exhibit peak power 306.1 mW cm −2 an ultra‐long cycling stability over 1200 h. Moreover, solid‐state laminated ZABs prepared presetting air flow layer show specific capacity 818.8 mA h , 520 h, wide temperature‐adaptive from −40 60 °C. This work not only offers possibilities metal‐loading for exploring efficient SACs, provides strategies device structure design toward advanced ZABs.

Language: Английский

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High entropy catalysts in electrolytic water splitting: A review from properties to applications

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 498, P. 155736 - 155736

Published: Sept. 12, 2024

Language: Английский

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Photocatalytic Semiconductor–Metal Hybrid Nanoparticles: Single-Atom Catalyst Regime Surpasses Metal Tips

ACS Nano, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 6, 2025

Semiconductor–metal hybrid nanoparticles (HNPs) are promising materials for photocatalytic applications, such as water splitting green hydrogen generation. While most studies have focused on Cd containing HNPs, the realization of actual applications will require environmentally compatible systems. Using heavy-metal free ZnSe-Au HNPs a model, we investigate dependence their functionality and efficiency cocatalyst metal domain characteristics ranging from single-atom catalyst (SAC) regime to metal-tipped The SAC was achieved via deposition individual atomic cocatalysts semiconductor nanocrystals in solution. Utilizing combination electron microscopy, X-ray absorption spectroscopy, photoelectron established presence single Au atoms ZnSe nanorod surface. Upon increased concentration, this transitions tip growth. Photocatalytic generation measurements reveal strong loading with sharp response maximum regime. Ultrafast dynamics show similar decay kinetics pristine nanorods either or tipped This indicates that transfer is not rate-limiting step process. Combined structural-chemical characterization, conclude enhanced activity due higher reactivity sites. holistic view establishes significance SAC-HNPs, setting stage designing efficient sustainable heavy-metal-free photocatalyst numerous applications.

Language: Английский

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Enhancing Efficiency and Durability of Alkaline Zn‐Co/Air Hybrid Batteries with Self‐Reconstructed Co/Co₂P Heterojunctions

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 29, 2024

Abstract Zn‐Co/air hybrid batteries showcase enhanced energy efficiency, power density, and stability compared to Zn‐air batteries. Nevertheless, it remains challenging fabricate multi‐functional cathode materials with fast reaction kinetics. Herein the synthesis of a wheat‐like composed “cereal‐grains” densely arranged Co/Co 2 P heterostructures grown on “central stems” P/N codoped carbon nanofibers (denoted as P@PNCF) is presented. The biomimetic nanostructures not only offer abundant exposed active sites maximize accessibility but also establish efficient multi‐channel networks for both electron transfer O /OH − diffusion. Furthermore, species high‐valent Co, resulting from self‐reconstruction heterojunction during first cycle, create Co 2+ ↔ 4+ redox pairs provide additional charging‐discharging voltage plateaus. In situ Raman spectroscopy measurement combined ex X‐ray diffraction evidence supports reversible process 3+/4+ x (OH) y K 2+/3+ , leading improved efficiency durability battery. As result, battery based P@PNCF exhibits remarkable density (321 mW cm −2 ), ultralong cycle (700 h), large (62% at 20 mA ).

Language: Английский

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Asymmetric Low-Coordination Tailoring of Single-Atom Cobalt Catalysts Enabling Efficient Oxygen Reduction Reaction

Nano Energy, Journal Year: 2025, Volume and Issue: unknown, P. 110776 - 110776

Published: Feb. 1, 2025

Language: Английский

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Triggering Synergistic Electronic Effect via Electron‐Directed Transfer within Pt_NPs‐Fe/NC Oxygen Reduction Catalyst for Zinc‐Air Batteries

Small, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 28, 2025

Abstract Rationally tuning Fe‐N‐C catalysts with synergistic nanoparticles for efficient oxygen reduction reaction (ORR) still remains challenging. Here, a nitrogen‐doped carbon‐supported bimetallic catalyst (Pt NPs ‐Fe/NC), combining atomically dispersed sites Pt nanoparticles, is synthesized. Experimental results reveal directional electron transfer between and Fe sites, which induces an effect, effectively modulating the density around sites. The modulation significantly enhances ORR catalytic activity of ‐Fe/NC. As result, ‐Fe/NC displays half‐wave potential 0.901 V (versus RHE) Tafel slope 59 mV dec −1 , surpassing performance commercial Pt/C demonstrating accelerated kinetics. In meantime, maintains excellent durability in terms stability as well. When assembled into liquid zinc‐air batteries (ZABs), delivers peak power 201.48 mW cm −2 specific capacity 809 mAh g . Additionally, ‐Fe/NC‐based flexible ZABs display outstanding discharge cycling stability. This work highlights effectiveness multiscale advancing provides valuable insights construction strategies energy storage applications.

Language: Английский

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sp-C induced regulation of the carboxyl ligand field strength to tailor Fe d-orbital for enhanced oxygen reduction

Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: unknown, P. 161001 - 161001

Published: March 1, 2025

Language: Английский

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Single‐Atom Co Meets Remote Fe for a Synergistic Boost in Oxygen Electrocatalysis

Advanced Energy Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 16, 2025

Abstract The oxygen electrocatalytic activity of transition metal catalysts can be tuned by tailoring their microstructure to optimize electronic configuration. Here, a one‐step Coordination‐Selective Synthesis strategy is developed integrate Co single‐atom sites and Fe‐based nanoparticles within the same matrix, enabling long‐range interactions that enhance Co‐N 4 reactivity improve reduction reaction performance. X‐ray absorption spectroscopy confirmed remote modulate electron distribution at sites. Structural characterizations reveal optimal catalyst, 50% Fe ‐NC, contains metallic Fe, 3 O , N species. Electrochemical measurements show it achieves onset half‐wave potentials 0.984 0.927 V versus RHE, surpassing 100% ‐NC with only Additionally, demonstrates efficient evolution performance, achieving an overpotential 298 mV 20 mA cm −2 comparable RuO 2 . Density functional theory calculations optimizes O‐containing intermediate adsorption/desorption, lowering theoretical overpotential. Zn‐air batteries assembled exhibited superior performance Pt/C, highlighting its potential for bifunctional electrocatalysis. This study provides approach designing high‐performance utilizing synergistic between atomic nanoscale

Language: Английский

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Engineering p–d Orbital Coupling and Vacancy-Rich Structure in Triatomic Iron–Bismuth–Iron Sites for Rechargeable Zinc–Air Batteries

ACS Nano, Journal Year: 2025, Volume and Issue: unknown

Published: April 29, 2025

The rational design of heteroatomic sites with synergistic electronic modulation remains a critical challenge for achieving bifunctional oxygen electrocatalysis in sustainable energy technologies such as fuel cells and metal-air batteries. Herein, triatomic Fe2BiN5 configuration embedded nitrogen-doped carbon (Fe2BiN5/C) atomically dispersed FeN2-BiN-FeN2 vacancy-rich structures is synthesized via pyrolysis etching strategy. architecture endows Fe2BiN5/C exceptional activity, delivering high reduction reaction half-wave potential 0.918 V an evolution overpotential 245 mV at 10 mA cm-2, surpassing Pt/C RuO2. In situ X-ray absorption fine structure Raman spectroscopy reveal dynamic structural during electrocatalysis, where Fe acts the primary active center Bi regulating electron distribution long-range interactions, thereby optimizing adsorption/desorption energetics intermediates. theoretical calculations further elucidate that Bi-induced p-d orbital coupling leads to alteration d-orbitals level, downshift d-band center, weaken binding strength oxygen-based intermediates, reduced barrier electrocatalysis. This work provides understanding site p-block metal modulators transition-metal atoms toward enhanced catalysis.

Language: Английский

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