Targeting Synthesis of Diatomic Catalysts by Selective Etching and Sequential Adsorption of Metal Atom

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

Diatomic catalysts featuring a tunable structure and synergetic effects hold great promise for various reactions. However, their precise construction with specific configurations diverse metal combinations is still challenging. Here, selective etching ion adsorption strategy proposed to accurately assign second atom (M2) geminal the single site (M1–Nx) constructing diatomic sites (e.g., Fe–Pd, Fe–Pt, Fe–Ru, Fe–Zn, Co–Fe, Co–Ni, Co–Cu). In this strategy, hydrogen peroxide selectively etches positively charged carbon atoms near M1–Nx moiety (denoted as α-C) produces vacancy, which could trap M2 at subsequent step. These show optimized electronic enhanced oxygen reduction activity compared single-site counterparts, representative Fe–Pd–NC Co–Fe–NC stand most active reaction (half-wave potential of 0.92 0.91 V, respectively). The α-C in single-atom reported here represents new post-treatment targeting synthesis sites.

Language: Английский

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Engineering the Lewis Acidity of Fe Single-Atom Sites via Atomic-Level Tuning of Spatial Coordination Configuration for Enhanced Oxygen Reduction

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 16, 2025

Nitrogen-doped carbon-supported Fe catalysts (Fe-N-C) with Fe-N4 active sites hold great promise for the oxygen reduction reaction (ORR). However, fine-tuning structure of to enhance their performance remains a grand challenge. Herein, we report an innovative design strategy promote ORR activity and kinetics by engineering Lewis acidity, which is achieved tuning spatial coordination geometry. Theoretical calculations indicated that Fe1-N4SO2 (with axial –SO2 group bonded Fe) offered favorable acidity ORR, leading optimized adsorption energies key intermediates. To implement this strategy, developed molecular-cage-encapsulated synthesize single-atom site catalyst (SAC) sites. In agreement theory, Fe1-N4SO2/NC demonstrated outstanding in both alkaline (E1/2 = 0.910 V 0.1 M KOH) acidic media 0.772 HClO4), surpassing commercial Pt/C traditional SACs Fe1-N4 or planar S-coordinated Fe1-N4-S Moreover, newly showed application potential quasi-solid-state Zn–air batteries, delivering superior across wide temperature range.

Language: Английский

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A bioinspired sulfur–Fe–heme nanozyme with selective peroxidase-like activity for enhanced tumor chemotherapy

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

Published: Dec. 5, 2024

Iron-based nanozymes, recognized for their biocompatibility and peroxidase-like activities, hold promise as catalysts in tumor therapy. However, concurrent catalase-like activity undermines therapeutic efficacy by converting hydrogen peroxide tissues into oxygen, thus diminishing hydroxyl radical production. Addressing this challenge, study introduces the hemin–cysteine–Fe (HCFe) nanozyme, which exhibits exclusive activity. Constructed through a supramolecular assembly approach involving Fmoc-l-cysteine, heme, Fe²⁺ coordination, HCFe distinctly incorporates heme [Fe–S] within its active center. Sulfur coordination to central Fe atom of Hemin is crucial modulating catalytic preference nanozyme towards This unique mechanism distinguishes from other bifunctional iron-based enhancing selectivity even beyond that natural peroxidases. selective allows significantly elevate ROS production exert cytotoxic effects, especially against cisplatin-resistant esophageal squamous cell carcinoma (ESCC) cells xenografts female mice when combined with cisplatin. These findings underscore HCFe's potential component multimodal cancer therapy, notably augmenting chemotherapy efficacy. nanozymes are promising therapy owing activity, but Here, authors address issue developing

Language: Английский

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Seeding Janus Zn–Fe Diatomic Pairs on a Hollow Nanobox for Potent Catalytic Therapy

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

Published: Jan. 27, 2025

Dual atomic nanozymes (DAzymes) are promising for applications in the field of tumor catalytic therapy. Here, integrating with ultrasmall Fe5C2 nanoclusters, asymmetric coordination featuring Janus Zn-Fe dual-atom sites an O2N2-Fe-Zn-N4 moiety embedded a carbon vacancy-engineered hollow nanobox (Janus ZnFe DAs-Fe5C2) was elaborately developed. Theoretical calculation revealed that synergistic effects Zn centers acting as both adsorption and active sites, oxygen-heteroatom doping, vacancy, nanoclusters jointly downshifted d-band center Fe 3d orbitals, optimizing desorption behaviors intermediates *OH, thereby significantly promoting activity. Upon 1064 nm laser irradiation, DAs-Fe5C2 superior photothermal conversion efficiency (η = 62.5%) showed thermal-augmented Fascinatingly, multienzymatic properties can suppress expression glutathione peroxidase 4 accelerate accumulation lipid peroxides, through which ferroptosis is triggered. Overall, tannin-involved will inspire more inventions biodegradable DAzymes therapy application.

Language: Английский

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Ligand-Restricted Strategy for Synthesizing Highly Pairing Dual Atom Catalysts

Research Square (Research Square), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 14, 2025

Dual atom catalysts (DACs), characterized by high activity and metal utilization, as well structural diversity with a large variety of catalytic sites, hold immense promise for energy conversion technologies, garnering substantial interest from both academia industry. However, achieving precise control manipulation atomic dispersion, pairing ratios, interatomic distances in DACs, which significantly affect their multifunctional properties, remains significant challenge. Herein, we developed ligand-restricted strategy the synthesis highly DACs tunable distances. This was accomplished coordinating diamine ligands dual precursors, restricting relative positions two atoms on two-dimensional graphitic carbon nitride. The ratio exceeded 82%, chain length molecules effectively regulating distance between paired atoms. As demonstration, Pt₁-Au₁ exhibited almost three times nitrate reduction to ammonia compared unpaired counterparts. Furthermore, shorter distanced DAC reveals four photothermal catalyzed hydrogenation reactions than longer ones. work not only introduces novel design atomic-scale fabrication complex but also provides valuable insights into nanoscale reaction mechanisms heterogeneous catalysis.

Language: Английский

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Biological Neural Network‐Inspired Micro/Nano‐Fibrous Carbon Aerogel for Coupling Fe Atomic Clusters With Fe‐N₄ Single Atoms to Enhance Oxygen Reduction Reaction

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

Published: March 5, 2025

Nitrogen-coordinated metal single atoms catalysts, especially with M-N4 configuration confined within the carbon matrix, emerge as a frontier of electrocatalytic research for enhancing sluggish kinetics oxygen reduction reaction (ORR). Nevertheless, due to highly planar D4h symmetry in M-N4, their adsorption behavior toward intermediates is limited, undesirably elevating energy barriers associated ORR. Moreover, structural engineering substrate also poses significant challenges. Herein, inspired by biological neural network (BNN), reticular nervous system high-speed signal processing and transmitting, comprehensive biomimetic strategy proposed tailoring Fe-N4 (Fe SAs) coupled Fe atomic clusters ACs) active sites, which are anchored onto chitosan microfibers/nanofibers-based aerogel (CMNCA-FeSA+AC) continuous conductive channels an oriented porous architecture. Theoretical analysis reveals synergistic effect SAs ACs optimizing electronic structures expediting The ingenious will shed light on topology optimization efficient electrocatalysts advanced electrochemical conversion devices.

Language: Английский

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Advancing polynary-atom catalysts: customization, preparation and utilization

Journal of Energy Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: March 1, 2025

Language: Английский

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Tuning Transition Metal 3d Spin state on Single‐atom Catalysts for Selective Electrochemical CO₂ Reduction

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

Published: March 13, 2025

Abstract Tuning transition metal spin states potentially offers a powerful means to control electrocatalyst activity. However, implementing such strategy in electrochemical CO 2 reduction (CO R) is challenging since rational design rules have yet be elucidated. Here we show how the addition of P dopants ferromagnetic element (Fe, Co, and Ni) single‐atom catalyst (SAC) can shift its state. For instance, with Fe SAC, enable switch from low state ( d x2‐ y2 0 , z2 xz yz 1 xy ) Fe‐N 4 high x2‐y2 3 ‐P. This studied using suite characterization efforts, including X‐ray absorption spectroscopy (XAS), electron resonance (ESR) spectroscopy, superconducting quantum interference device (SQUID) measurements. When used for R, SAC ‐P active sites yields > 90% Faradaic efficiency over wide potential window ≈530 mV maximum partial current density ≈600 mA cm −2 . Density functional theory calculations reveal that 3+ exhibits enhanced back donation via / ‐π* bond, which enhances * COOH adsorption promotes formation. Taken together, results intentionally tuned boost R performance.

Language: Английский

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Cascade Hydrogen Peroxide Reduction Reaction Endows Cu‐Fe Dual‐Atom Catalyst with Durable Oxygen Reduction Performance

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

Published: March 27, 2025

Abstract Durable problems caused by the attack from free radicals are considered as Achilles’ heel in practical applications for oxygen reduction reaction (ORR) acidic conditions. Herein, a ligand‐bridging strategy is proposed to design Cu─Fe dual‐atom catalyst (CuFeDAC‐NC) relieve undesirable degradation radicals. Comprehensive investigations and theoretical calculations verify that byproduct of hydrogen peroxide can be effectively eliminated at neighboring Cu sites through cascade catalytic process, formation oxidative suppressed, leading enhanced durability. Meanwhile, synergistic effect between site Fe results superior ORR performance. CuFeDAC‐NC delivers half‐wave potential ( E 1/2 ) 0.811 V 0.1 M HClO 4 electrolyte exhibits excellent durability with small loss 12 mV after 10 000 cycles Fe─NC (34 mV). This work not only provides new perspective get insight into mechanisms but also opens an avenue catalysts

Language: Английский

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Homonuclear/Heteronuclear Bimetallic Conjugated Coordination Polymers with Customized Oxygen Evolution Pathway

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: April 11, 2025

The reasons for the generally superior performance of synergistic effects in bimetallic catalysts oxygen evolution reaction (OER) are not fully understood, largely due to complexity catalyst structures and challenges associated with synthesizing long-range atomic ordering catalysts. In this study, we present a series two-dimensional (2D) conjugated coordination polymers (c-CPs) involving Co or Ni unambiguous nearly identical geometry electrocatalysis OER, which highly suitable discussions on structure-property correlations. heteronuclear CoNi-PI unexpectedly alters OER catalytic mechanisms from adsorbate mechanism those observed homonuclear CoCo-PI NiNi-PI kinetically faster oxide path mechanism, exhibiting high stability an ultralow overpotential 282 mV even at 100 mA cm-2 Tafel slope approximately 42 dec-1. This study presents extremely rare crystalline excellent properties, promising significant influences development research.

Language: Английский

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