Mesoporous Boron‐Doped Carbon with Curved B₄C Active Sites for Highly Efficient H₂O₂ Electrosynthesis in Neutral Media and Air‐Supplied Environments

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

Published: Jan. 15, 2025

Abstract Hydrogen peroxide (H 2 O ) electrosynthesis via the 2e − oxygen reduction reaction (ORR) is considered as a cost‐effective and safe alternative to energy‐intensive anthraquinone process. However, in more practical environments, namely, use of neutral media air‐fed cathode slow ORR kinetics insufficient supply pose significant challenges efficient H production at high current densities. In this work, mesoporous B‐doped carbons with novel curved B 4 C active sites, synthesized carbon dioxide (CO using pore‐former agent, simultaneously achieve excellent activity improved mass transfer properties are introduced. Through combination experimental analysis theoretical calculations, it confirmed that configuration, formed by mesopores carbon, demonstrates superior selectivity for due its weaker interaction *OOH intermediates compared planar media. Moreover, facilitate suppress hydrogen evolution reaction, achieving Faradaic efficiency 86.2% 150 mA cm −2 under air‐supplied conditions, along an impressive utilization 93.6%. This approach will provide route catalyst design environment.

Language: Английский

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Dual-Isolation Effect of Bismuth in Non-Noble BiNi Alloys for Enhanced Performance in H₂O₂ Electrosynthesis

ACS Catalysis, Journal Year: 2025, Volume and Issue: 15(3), P. 1819 - 1828

Published: Jan. 17, 2025

Noble-metal alloys are high-efficiency two-electron oxygen reduction reaction (2e– ORR) catalysts for the electrochemical production of H2O2. However, development noble-metal H2O2 is still in a bottleneck period due to their high cost, toxicity, low atom utilization, and limited reactivity. To solve these dilemmas alloys, developing non-noble can be an alternative. Herein, BiNi with uniform diameter ∼11 nm supported on carbon nanosheets (BiNi/C) synthesized by hydrothermal-pyrolysis method. The BiNi/C material exhibits 2e– ORR performance onset potential 0.76 V vs RHE selectivity ∼98% 0.1 M KOH. H-cell tests deliver yield ∼17 mM within 2 h at 0.4 RHE. then used fixed-bed Fenton process, degradation efficiencies RhB BPA maintain 100% ∼95% 10 h, respectively. Theoretical calculations reveal that Bi regulate electronic structure Ni through "dual-isolation" effect physical isolation. adsorption energy *OOH thus deceased, side-on sites achieved. Furthermore, itself lowest overpotential also serve as active site generation dual-isolation effect. Our study provides guidance synthesis alloy activity selectivity.

Language: Английский

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Observation of O₂ Molecules Inserting into Fe–H Bonds in a Ferrous Metal–Organic Framework

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

Published: Jan. 21, 2025

Exploring the interactions between oxygen molecules and metal sites has been a significant topic. Most previous studies concentrated on enzyme-mimicking interacting with O2 to form M-OO species, leaving development of new types O2-activating novel adsorption mechanisms largely overlooked. In this study, we reported an Fe(II)-doped metal-organic framework (MOF) [Fe3Zn2H4(bibtz)3] (MAF-203, H2bibtz = 1H,1'H-5,5'-bibenzo[d][1,2,3]triazole), featuring unprecedented tetrahedral Fe(II)HN3 site. This MOF exhibits selective behavior for from air, achieving O2/N2 separation selectivity up 67.1. Breakthrough experiments confirmed that MAF-203 can effectively capture air even under high relative humidity 60%. X-ray absorption spectroscopy, in situ diffuse reflectance infrared Fourier transform spectra, ab initio molecular dynamics simulations were utilized monitor loading process Interestingly, could insert into Fe-H bonds FeIIHN3 sites, forming FeIII-OOH species (instead commonly observed Fe-OO species) ultrahigh enthalpy -99.2 kJ mol-1. Consequently, enables efficient electrochemical 2e- reduction production H2O2 as feedstock. Specifically, solid-state electrolyte electrolyzer without any liquid electrolyte, achieved continuous medical-grade (3.2 wt %) solution salts 70 h, performance comparable pure conditions. The activation inaugurate fresh chapter grasping interaction sites.

Language: Английский

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Oxide-modified bifunctional carbonaceous cathode: oxygen-rich alkaline-like microenvironment strengthened hydrogen peroxide as an electron donor to enhance Fe3+ reduction in Fe(III) electro-Fenton

Process Safety and Environmental Protection, Journal Year: 2025, Volume and Issue: 196, P. 106847 - 106847

Published: Feb. 7, 2025

Language: Английский

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Balancing the Aggregation of Cobalt Phthalocyanine on Carbon Nanohorn for Efficient H₂O₂ electrosynthesis in Neutral Electrolyte

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

Published: Feb. 7, 2025

Abstract Oxygen reduction reaction (ORR) driven by renewable electricity in neutral electrolyte presents a promising way for generating H 2 O , which is suitable daily sanitation and hygiene management. Cobalt phthalocyanine (CoPc) serves as an effective molecular electrocatalyst, providing active sites to facilitate generation during ORR through uniform distribution on carbon supports. However, the catalytic performance currently falls short of industrial application requirements. Herein, we employed nanohorns with abundant oxygen functional groups (CNH(O)) support CoPc, thereby optimizing CoPc enhancing electron‐deficient Co centres. Control experiments characterizations demonstrate centres dependent degree aggregation, highlighting trade‐off between loading weight CoPc. Then, 4% CNH(O) exhibited optimal generation, achieving current density 483 mA cm −2 at potential 0.3 V vs RHE Faradaic efficiency 64 %.

Language: Английский

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Electrochemical Pilot H₂O₂ Production by Solid‐State Electrolyte Reactor: Insights From a Hybrid Catalyst for 2‐Electron Oxygen Reduction Reaction

Angewandte Chemie International Edition, Journal Year: 2025, Volume and Issue: unknown

Published: March 10, 2025

The electrochemical oxygen reduction reaction (ORR) offers an alluring and sustainable alternative to the traditional anthraquinone process for hydrogen peroxide (H₂O₂) synthesis. However, challenges remain in developing scalable electrocatalysts cost-effective reactors high-purity H₂O₂ production. This study introduces a simple yet effective mechanical mixing method fabricate hybrid electrocatalyst from oxidized carbon nanotubes layered double hydroxides (LDHs). easily accessible low-cost catalyst achieves near-perfect Faradaic efficiency (∼100%) with low overpotentials of 73 mV at 10 mA cm⁻2 588 400 solid electrolyte cell. Through theoretical calculations in-situ analyses, we uncover pivotal role played by LDH co-catalyst fine-tuning local pH catalyst/solid-electrolyte interface that drives both activity selectivity. We also design solid-state reactor using cation-exchange resin (CER) as proton conductor microchannel efficient mass transfer, achieving production rate 5.29 mmol h⁻¹ continuous output concentrations 11.8 wt.% H₂O₂. Scaled industrial area 2 × 100 cm2, pilot impressive approximately 127.0 15 A, marking significant advancement

Language: Английский

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Electrochemical Pilot H₂O₂ Production by Solid‐State Electrolyte Reactor: Insights From a Hybrid Catalyst for 2‐Electron Oxygen Reduction Reaction

Angewandte Chemie, Journal Year: 2025, Volume and Issue: unknown

Published: March 10, 2025

Abstract The electrochemical oxygen reduction reaction (ORR) offers an alluring and sustainable alternative to the traditional anthraquinone process for hydrogen peroxide (H₂O₂) synthesis. However, challenges remain in developing scalable electrocatalysts cost‐effective reactors high‐purity H₂O₂ production. This study introduces a simple yet effective mechanical mixing method fabricate hybrid electrocatalyst from oxidized carbon nanotubes layered double hydroxides (LDHs). easily accessible low‐cost catalyst achieves near‐perfect Faradaic efficiency (∼100%) with low overpotentials of 73 mV at 10 mA cm⁻ 2 588 400 solid electrolyte cell. Through theoretical calculations in‐situ analyses, we uncover pivotal role played by LDH co‐catalyst fine‐tuning local pH catalyst/solid‐electrolyte interface that drives both activity selectivity. We also design solid‐state reactor using cation‐exchange resin (CER) as proton conductor microchannel efficient mass transfer, achieving production rate 5.29 mmol h⁻¹ continuous output concentrations 11.8 wt.% H₂O₂. Scaled industrial area × 100 cm , pilot impressive approximately 127.0 15 A, marking significant advancement

Language: Английский

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Metalloenzyme‐Inspired Cluster Fabrication within Mesoporous Channels Featuring Optimized Catalytic Microenvironments for Efficient Neutral pH H₂O₂ Electrosynthesis

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

Published: March 17, 2025

Abstract In nature, some metalloenzymes facilitate highly efficient catalytic transformations of small molecules, primarily attributed to the effective coupling between their metal cluster active sites and surrounding microenvironment. Inspired by this, a thermotropic redispersion strategy incorporate bismuth nanoclusters (Bi NCs) into mesoporous channels, mimicking metalloenzyme‐like catalysis enhance two‐electron oxygen reduction reaction (2e − ORR) for neutral pH H 2 O electrosynthesis, is developed. This model electrocatalyst exhibits exceptional 2e ORR performance with >95% selectivity across 0.2–0.6 V vs RHE in electrolyte. Notably, system produces up 7.2 wt% solution at an industrially relevant current density ≈320 mA cm −2 , 90% Faradaic efficiency over 120 h flow cell, demonstrating significant practical potential. Mechanistic insights reveal that introduction Bi NCs enhances adsorption *OOH intermediate, facilitating process. Moreover, channels carbon support create favorable microenvironment aeration local alkalinity, further boosting productivity. catalyst design mimics optimal integration site microenvironment, offering valuable rational nature‐inspired small‐molecule catalysts.

Language: Английский

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Tuning the Formation Kinetics of *OOH Intermediate with Hollow Bowl-Like Carbon by Pulsed Electroreduction for Enhanced H₂O₂ Production

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

Published: March 28, 2025

The electrochemical synthesis of hydrogen peroxide (H2O2) via the two-electron oxygen reduction reaction (2e- ORR) is a promising alternative to conventional anthraquinone method. However, due local alkalinization near catalyst surface, restricted replenishment and insufficient activated water molecule supply limit formation key *OOH intermediate. Herein, pulsed electrocatalysis approach based on structurally optimized S/N/O tridoped hollow carbon bowl has been proposed overcome this challenge. In an H-type electrolytic cell, method achieves superior H2O2 yield rate 55.6 mg h-1 mgcat.-1, approximately 1.6 times higher than potentiostatic (34.2 mgcat.-1), while maintaining Faradaic efficiency above 94.6%. situ characterizations, finite element simulations, density functional theory analyses unveil that application potentials mitigates OH- concentration, enhances activation proton generation, facilitates production within bowl-like structure. These effects synergistically accelerate kinetics intermediate by efficient generation *O2 *H2O intermediates, leading yields. This work develops strategy tune catalytic environments for diverse applications.

Language: Английский

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Regulating the Local Reaction Microenvironment at Chromium Metal–Organic Frameworks for Efficient H₂O₂ Electrosynthesis in Neutral Electrolytes

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

Published: March 30, 2025

Abstract The electrochemical synthesis of hydrogen peroxide represents a promising alternative to the traditional anthraquinone process, aiming for zero pollution. However, achieving efficient in neutral electrolytes is challenging due sluggish kinetics two‐electron oxygen reduction reaction. To address this issue, unique metal–organic framework (MOF) featuring Cr metal sites coordinated with tetrabromoterephthalic acid (Cr‐TBA) synthesized. This specially designed MOF exhibits distinctive paper‐clip‐like structure and remarkably enhanced Lewis acidity. Experimental results demonstrate that obtained can facilitate attraction OH − ions solution, promoting their accumulation on catalyst surface. enhancement leads excellent performances Cr‐TBA electrolytes, Faradaic efficiencies 96–98% production rate 13.4 mol g cat −1 h at current density 150 mA cm −2 . Operando spectroscopy functional theory calculations indicate modified microenvironment effectively facilitates conversion * OOH intermediates H 2 O

Language: Английский

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