Enhancing Compatibility of Two‐Step Tandem Catalytic Nitrate Reduction to Ammonia Over P‐Cu/Co(OH)₂

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

Published: Sept. 11, 2024

Abstract Electrochemical nitrate reduction reaction (NO 3 RR) is a promising approach to realize ammonia generation and wastewater treatment. However, the transformation from NO − NH involves multiple proton‐coupled electron transfer processes by‐products 2 , H etc.), making high selectivity challenge. Herein, two‐phase nanoflower P‐Cu/Co(OH) electrocatalyst consisting of P‐Cu clusters P‐Co(OH) nanosheets designed match two‐step tandem process ) more compatible, avoiding excessive accumulation optimizing whole reaction. Focusing on initial 2e process, inhibited * desorption Cu sites in gives rise appropriate released electrolyte. Subsequently, exhibits superior capacity for trapping transforming desorbed during latter 6e due thermodynamic advantage contributions active hydrogen. In 1 m KOH + 0.1 leads yield rate 42.63 mg h cm Faradaic efficiency 97.04% at −0.4 V versus reversible hydrogen electrode. Such well‐matched achieves remarkable synthesis performance perspective catalytic reaction, offering novel guideline design RR electrocatalysts.

Language: Английский

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Spatially Separated Cu/Ru on Ordered Mesoporous Carbon for Superior Ammonia Electrosynthesis from Nitrate over a Wide Potential Window

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(36), P. 24966 - 24977

Published: Aug. 28, 2024

Nitrate (NO3–) in wastewater poses a serious threat to human health and the ecological environment. The electrocatalytic NO3– reduction ammonia (NH3) reaction (NO3–RR) emerges as promising carbon-free energy route for enabling removal sustainable NH3 synthesis. However, it remains challenge achieve high Faraday efficiencies at wide potential window due complex multiple-electron process. Herein, spatially separated dual-metal tandem electrocatalysts made of nitrogen-doped ordered mesoporous carbon support with ultrasmall high-content Cu nanoparticles encapsulated inside large low-content Ru dispersed on external surface (denoted Ru/Cu@NOMC) are designed. In NO3–RR, sites can quickly convert adsorbed NO2– (*NO2–), while efficiently produce active hydrogen (*H) enhance kinetics converting *NO2– sites. Due synergistic effect between sites, Ru/Cu@NOMC exhibits maximum Faradaic efficiency (FENH3) approximately 100% −0.1 V vs reversible electrode (RHE) yield rate 1267 mmol gcat–1 h–1 −0.5 RHE. Finite element method (FEM) simulation electrochemical situ Raman spectroscopy revealed that framework intermediate concentration confinement effect. Thanks Cu–Ru mesopore effect, 500 mV FENH3 over 90% superior stability production 156 h be achieved catalyst.

Language: Английский

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Dynamically Restructuring Nanoporous Cu–Co Electrocatalyst for Efficient Nitrate Electroreduction to Ammonia

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(16), P. 12251 - 12259

Published: Aug. 1, 2024

The electrochemical nitrate (NO3–) reduction reaction (NITRR) to ammonia (NH3) offers an environmentally friendly alternative for NH3 synthesis but suffers from limited yield and low Faradaic efficiency (FE) due the sluggish kinetics of hydrogenation process. Herein, nanoporous Cu/CoOOH heterostructure is reported as efficient electrocatalyst NITRR. catalyst achieves a high rate 275.9 μmol h–1 cm–2 (689.8 mmol gcat–1) 836.8 (2092.0 gcat–1), with corresponding FE values 85.3 91.5% in 200 1400 ppm NO3–-N electrolyte, respectively. In situ Raman spectra reveal that derived synergistic chemical/electrochemical redox between NO3– CuCo alloy during NITRR Theoretical simulations indicate exhibits enhanced *NO2 affinity reduces energy barrier rate-determining *NO2H formation step, effectively facilitating NH3.

Language: Английский

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Hydrogen Spillover Mechanism at the Metal–Metal Interface in Electrocatalytic Hydrogenation

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(38)

Published: July 3, 2024

Hydrogen spillover in metal-supported catalysts can largely enhance electrocatalytic hydrogenation performance and reduce energy consumption. However, its fundamental mechanism, especially at the metal-metal interface, remains further explored, impeding relevant catalyst design. Here, we theoretically profile that a large free difference hydrogen adsorption on two different metals (|ΔG

Language: Английский

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AuCu Nanodendrite for Enhancing Electrocatalytic Nitrate Reduction Applications via Two-stage Microfluidic Fabrication Strategy

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 1230 - 1241

Published: Jan. 7, 2025

The electrocatalytic nitrate reduction reaction (NitrRR) has attracted great attention in clean ammonia production, but it unsatisfactory selectivity and sluggish dynamics, owing to the complex eight-electron transfer process. While dendritic AuCu alloy is anticipated offer competitive performance, significant challenges remain terms of insufficient structural regulation an unelucidated enhancement mechanism because complexity involved its preparation. To address these issues, we have developed a two-stage microfluidic platform that facilitates stable fabrication controllable nano dendrites (NDs). Notably, Cu content resultant NDs reaches impressive 35.34 At%, surpassing traditional liquid-phase limitations. Furthermore, dendrite structure been thoroughly validated, revealing clear structure–activity relationship. By employing precise manipulation, determined optimal composition NDs, achieving remarkable yield 21.93 mg h–1 cm–2 faradic efficiency 93.30%. Additionally, DFT calculations further elucidate performance mechanism, showing Au3Cu1 sites significantly reduce energy barrier (0.28 eV) rate-determining step (RDS: *NO → *HNO), while excessive deposition adverse effect. Our work contributes innovative guidance for design high-performance electrocatalysts.

Language: Английский

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Controlling electrocatalytic nitrate reduction efficiency by utilizing dπ–pπ interactions in parallel stacking molecular systems

Chemical Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

The orientation of β-CuPc favours the overlap central Cu with N parallel molecules, which is reason behind high electrical conductivity and selectivity in NH 3 production via nitrate reduction, impossible other polymorphs.

Language: Английский

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Revealing the Tandem Behavior of Iron‐Group/Copper Binary Catalysts in the Electroreduction of Nitrate to Ammonia

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

Published: March 16, 2025

Abstract As a green strategy for both ammonia (NH 3 ) production and wastewater purification, electrochemical reduction of nitrate (NO RR) faces challenges due to the nitrite 2 − accumulation competitive hydrogen evolution reaction (HER). Tandem catalysis NO NH offers great potential enhancing selectivity. Herein, iron‐group (Fe, Co, or Ni) nanosheets are introduced onto Cu nanowires construct Cu‐Fe, Cu‐Co, Cu‐Ni tandem systems respectively. Specifically, sites facilitate conversion . Fe sites, similar Cu, reduce , exacerbating rather than converting it their inability precisely capture Co exhibiting excellent moderate HER activity, can seamlessly operate with realize well‐ordered relay catalysis, which achieves superior yield rate 48.44 mg h −1 cm −2 Ni demonstrate removal capability at low overpotentials, leading Faraday efficiency 99.47%. However, its remarkable HER‐active property demonstrated via in situ polarization imaging makes challenge ampere‐level current densities. This work identifies behavior coupled providing reference design further optimization system.

Language: Английский

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Enhanced nitrite electroreduction to ammonia via interfacial dual-site adsorption

Journal of Energy Chemistry, Journal Year: 2024, Volume and Issue: 96, P. 328 - 335

Published: May 13, 2024

Language: Английский

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Ni_0.25Cu_0.5Sn_0.25 Nanometallic Glasses As Highly Efficient Catalyst for Electrochemical Nitrate Reduction to Ammonia

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

Published: Oct. 1, 2024

Abstract Electrochemical nitrate reduction to ammonia (NRA) is a promising approach for alleviating energy crisis and water pollution. Current NRA catalysts are challenged simultaneously improve the rate of adsorption desorption processes further increase total activity due Brønsted−Evans−Polanyi (BEP) relationships. Herein, two‐step Joule heating method utilized preparation Ni 0.25 Cu 0.5 Sn nanometallic glass containing synergistic catalytic sites enhance processes. Kelvin probe force microscopy reveals pronounced oscillatory behavior in surface potential glass, which an important feature site, empirical formula proposed quantitatively characterize its characteristic. In situ electrochemical Raman spectroscopy indicates promotion nickel tin atoms processes, respectively. DFT calculations demonstrated that presents wide range distributions favor multisite catalysis. The present work provides new ideas design understanding highly active catalysts.

Language: Английский

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Electrochemical reduction of nitrate to Ammonia: Recent progress and future directions

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 495, P. 153108 - 153108

Published: June 13, 2024

Language: Английский

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