Hollow Square Ni-Doped Copper Oxide Catalyst Boosting Electrocatalytic Nitrate Reduction

ACS Catalysis, Год журнала: 2025, Номер 15(3), С. 1672 - 1683

Опубликована: Янв. 16, 2025

The electrochemical nitrate reduction reaction to ammonia (NRA) is gaining increasing attention as an eco-friendly approach convert harmful pollutants into high-value product ammonia. NRA involves two critical rate-determining steps: hydrogenation of the *NO and *NOH intermediates. composite Ni Cu has been demonstrated exhibit synergistic catalytic effects; however, research on combination CuO remains limited. Herein, advanced Ni-doped copper oxide catalyst with a hollow square morphology (Ni–CuO) reported Faradaic efficiency 95.26% at −0.8 V vs RHE high yield rate 0.94 mmol h–1 cm–2, demonstrating selectivity stability. Complementary analyses that active hydrogen generated sites facilitates *NOx adsorbed sites. Theoretical computations further confirm thermodynamic viability this bimetallic mechanism. Furthermore, Al–NO3– battery open-circuit voltage was constructed by using Ni–CuO cathode. This work presents synergistically modulated for complex processes introduces highly efficient capable simultaneous NH3 synthesis electrical energy conversion, underscoring its potential in catalysis development chemical industries.

Язык: Английский

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Coupling Nitrate‐to‐Ammonia Conversion and Sulfion Oxidation Reaction Over Hierarchical Porous Spinel MFe₂O₄ (M═Ni, Co, Fe, Mn) in Wastewater

Small, Год журнала: 2025, Номер unknown

Опубликована: Янв. 7, 2025

The construction of coupled electrolysis systems utilizing renewable energy sources for electrocatalytic nitrate reduction and sulfion oxidation reactions (NO3RR SOR), is considered a promising approach environmental remediation, ammonia production, sulfur recovery. Here, simple chemical dealloying method reported to fabricate hierarchical porous multi-metallic spinel MFe2O4 (M═Ni, Co, Fe, Mn) dual-functional electrocatalysts consisting Mn-doped NiFe2O4/CoFe2O4 heterostructure networks Ni/Co/Mn co-doped Fe3O4 nanosheet networks. excellent NO3RR with high NH3 Faradaic efficiency 95.2% at -0.80 V versus reversible hydrogen electrode (vs RHE) yield rate 608.9 µmol h-1 cm-2 -1.60 vs RHE, impressive SOR performance (100 mA [email protected] achieved MFe2O4. Key intermediates such as *NO, *NH2, are identified in the process by situ Fourier transform infrared spectroscopy (in FTIR). MFe2O4-assembled two-electrode coupling system (NO3RR||SOR) shows an ultra-low cell voltage 1.14 10 cm-2, much lower than NO3RR||OER (oxygen evolution reaction, [email protected] V), simultaneously achieving two expected targets value-added generation recovery, also demonstrating durability 18 h. This work demonstrates great potential ferrite-based catalysts remediation.

Язык: Английский

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Efficient Electrocatalytic Conversion of Nitrate in Water with Anderson-Type Polyoxometalate-Modified Co-MOF

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Март 6, 2025

The electrochemical conversion of nitrate to ammonia has garnered growing attention, as it aims reduce carbon emissions and promote environmental sustainability. Nevertheless, developing an electrocatalyst that exhibits outstanding activity, selectivity, stability is still a significant challenge. Here, we report three Anderson-type polyoxometalates (POMs)-modified cobalt metal-organic framework (Co-MOF), namely, Co-MOF/MMo6 (M = Fe, Co, Ni) composite electrocatalyst, fabricated using easy standing method. Among them, POMs not only facilitated the formation lamellar structures with high specific surface area Co-MOF morphology regulator but also contributed electron transfer between electron-rich cluster, achieving enhancement in catalytic performance NO3RR NH3. In particular, Co-MOF/NiMo6 maximal Faradaic efficiency 98.2% at -0.8 V vs reverse hydrogen electrode (vs reversible (RHE)) NH3 yield rate up 10.88 mg h-1 mgcat.-1, better than most previously reported MOF-based catalysts. By situ spectrometric measurement, demonstrate via kinetically favored pathway NO3- → *NO3 *NO2 *NO *NH2OH *NH3. This work indicates considerable potential POM-based MOF materials for

Язык: Английский

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Activating the Basal Planes of Ti₂C MXene for Accelerated Ammonia Electrosynthesis: Role of Surface Terminations

Small, Год журнала: 2025, Номер unknown

Опубликована: Янв. 2, 2025

Abstract Altering the edge sites of 2D MXenes for electrochemical dinitrogen reduction reaction (ENRR) is widely reported, whereas activation its relatively inert basal planes neglected. Herein, and optimization Ti 2 CT x (T = *F, *O, *OH) toward enhanced ENRR to ammonia reported. The balanced surface functionalization in regulates kinetics by regulating potential zero charge (E PZC ) work function (). Specifically, altered E enhances electric field localization screening at /water interface stabilizing transition state reducing energy (ΔE). Hydrodynamic voltammetry, situ Raman, post‐ENRR X‐ray spectroscopy suggest faster kinetics, via an associative distal pathway, with *OH *F terminated 3+ as dominant active over surface. achieves yield 35.2 Faradaic efficiency 5.9% 0.05 m H SO 4 , which further improves 49% 0.5 NaBF . strategy concurrently modulates via, proton‐repelling functional groups (*F) on electrode weak proton donor electrolytes (NaBF ). This suppresses HER minimizes competition sites, promotes selective nitrogen activation, thereby boosting efficiency.

Язык: Английский

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Highly graphitized nitrogen-doped ordered mesoporous carbon supported Ni nanocrystals for efficient hydrazine-assisted CO2 splitting

Journal of Materials Chemistry A, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 26, 2024

An efficient nanoscale Ni-based catalyst enabled the energy-efficient coupling of HzOR with CO 2 RR for production.

Язык: Английский

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Cobalt Nanoparticles Encapsulated in N-Doped Carbon Nanotubes Assembled on Carbon Cloth for Efficient Electroreduction of Nitrite to Ammonia

Industrial & Engineering Chemistry Research, Год журнала: 2025, Номер unknown

Опубликована: Янв. 24, 2025

Electrochemical nitrite (NO2–) reduction provides an alternative pathway for both sustainable ammonia (NH3) synthesis and reutilization of NO2– pollutants, but this process requires high activity selective catalysts. In work, cobalt nanoparticles encapsulated in N-doped carbon nanotubes supported on cloth (Co@NCNT/CC) as a low-cost electrocatalyst can efficiently catalyze NO2–-to-NH3 conversion. Such Co@NCNT/CC shows exceptional electrocatalytic performance, achieving maximum NH3 Faradaic efficiency 94.9% with yield 365.1 μmol h–1 cm–2 at −0.3 V. Remarkably, the assembled Zn–NO2– battery cathode exhibits peak power density 4.4 mW satisfactory 141.5 cm–2.

Язык: Английский

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Modifying Microenvironment in Van der Waals Gap by Cu/N Co‐Doping Strategy for Highly Efficient Nitrite Reduction to Ammonia

Advanced Science, Год журнала: 2025, Номер unknown

Опубликована: Фев. 24, 2025

Abstract Electroreduction of nitrite to ammonia has significant promise for economical NH 3 electrosynthesis and wastewater treatment. Herein, sulfur vacancies rich Cu─N co‐doped SnS 2 nanosheet is designed as a highly active durable NO RR catalyst. Benefiting from the strategy, Cu/N‐SnS 2‐x achieves highest yield rate 18.15mg h −1 mg cat at −0.935 V (vs RHE) excellent Faradaic Efficiency 95.73% −0.835 RHE). In situ FT‐IR in XPS proves that greater capacity atomic hydrogen generation, which facilitates conversion maintains structural stability during process. Theoretical calculations reveal introduced effectively expose metal atoms inside make them adsorb efficiently, accelerates transformation ammonia. Besides, Cu N can form new electronic structure, induces an electron‐deficient state promotes adsorption reaction intermediates on Cu, reduces energy barrier reduction surface. The current exploration presents fresh prospects rational development effective electrocatalyst synthesizing nitrite.

Язык: Английский

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Electrodeposited P‐Doped CuNi Alloy from Deep Eutectic Solvent for Efficient and Selective Nitrate‐to‐Ammonia Electroreduction

Small, Год журнала: 2025, Номер unknown

Опубликована: Март 7, 2025

Electrochemical nitrate reduction reaction (NO3RR) offers a promising alternative for ammonia production using electricity generated from renewable energy sources. Active electrocatalysts with high selectivity and yield are required to selectively catalyze NO3RR ammonia. Here, P-doped Cu0.51Ni0.49 alloy thin films electrodeposited deep eutectic solvent of choline chloride-ethylene glycol (ChCl/EG). The P-Cu0.51Ni0.49 produces 1616.94 µg h-1 cm-2 at -0.55 VRHE (V versus reversible hydrogen electrode), Faradaic efficiency 98.38% 97.84% -0.25 VRHE, much better than the P-Ni P-Cu prepared under similar condition. rate, originated number electrochemically active sites more facile kinetics. Mechanistic study density functional theory calculation proves that exhibits higher conductivity NO3 - adsorption compared P-Cu, induced by electron interaction. Characterizations after cycling show crystallinity decreases, content divalent metal ions increases surface. is an stable material electrocatalyze in neutral aqueous solutions.

Язык: Английский

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Work Function-Induced Electronic Modulation in NiCo Alloy for Electrochemical Nitrate Reduction

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Апрель 3, 2025

The rational design of electrocatalysts is great significance in the production ammonia (NH3) through a nitrate reduction reaction (NO3-RR). This article proposes approach to regulate electron redistribution and intermediate adsorption energy by adjusting work function alloy compounds. As an example, NiCo successfully electrodeposited on carbon cloth (CC) using deep eutectic solvent (DES) as medium. results show that rate high 1.55 mmol h-1 cm-2 at -0.38 V vs RHE, with Faraday efficiency be 84.94%, selectivity 94%. Experimental characterizations combined density functional theory calculations confirm alloying beneficial for reducing Ni. turn adjusts d-band center Fermi level, changes rate-determining step during process, consequently improves performance. Eventually, investigation conducted Zn-NO3- battery fabricated Ni1Co2/CC. further exhibits potential Ni1Co2/CC within conversion equipment. study brings fresh concepts opportunities development novel NO3-RR.

Язык: Английский

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Cu mediated defect manipulation in MIL-88A(Fe) for boosting photocatalytic N2 fixation

Journal of Colloid and Interface Science, Год журнала: 2025, Номер unknown, С. 137504 - 137504

Опубликована: Апрель 1, 2025

Язык: Английский

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