Tunable NiSe‐Ni₃Se₂ Heterojunction for Energy‐Efficient Hydrogen Production by Coupling Urea Degradation

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

Published: Jan. 7, 2025

Abstract Urea‐assisted water splitting is a promising energy‐saving hydrogen (H 2 ) production technology. However, its practical application hindered by the lack of high‐performance bifunctional catalysts for urea oxidation reaction (UOR) and evolution (HER). Herein, heterostructured catalyst comprising highly active NiSe Ni 3 Se , along with conductive graphene‐coated nickel foam skeleton (NiSe‐Ni /GNF) reported. The NiSe‐Ni originates from in situ selenization foam, allowing careful regulation to ratio simply adjusting calcination temperature. Theoretical calculations charge transfer between components can optimize pathways reduce corresponding energy barriers. Accordingly, designed exhibits excellent UOR HER activity stability. Furthermore, /GNF‐based UOR‐HER electrolyzer requires only 1.54 V achieve current density 50 mA cm −2 which lower than many recent reports much 1.83 OER‐HER electrolyzers. Moreover, exhibited negligible cell voltage variation during 28‐h stability test, indicating satisfactory stability, provides new viable paradigm H production.

Language: Английский

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

ACS Catalysis, Journal Year: 2025, Volume and Issue: 15(3), P. 1672 - 1683

Published: Jan. 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.

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

Published: Jan. 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.

Language: Английский

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Efficient Nitrate to Ammonia Conversion on Bifunctional IrCu₄ Alloy Nanoparticles

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

Published: Jan. 18, 2025

Electrochemical nitrate reduction (NO3RR) to ammonia presents a promising alternative strategy the traditional Haber-Bosch process. However, competitive hydrogen evolution reaction (HER) reduces Faradaic efficiency toward ammonia, while oxygen (OER) increases energy consumption. This study designs IrCu4 alloy nanoparticles as bifunctional catalyst achieve efficient NO3RR and OER suppressing unwanted HER. is achieved by operating at positive potentials using catalyst, which allows of 93.6% for NO3RR. When applied catalysis, also shows excellent results, with relatively low overpotential 260 mV 10 mA cm-2. Stable production can be 50 h in 16 cm2 flow electrolyzer simulated working conditions. Our research provides pathway optimizing through catalysts tandem approach.

Language: Английский

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Green Ammonia Unleashed: Cutting-Edge Electrochemical Synthesis, Catalyst Innovations, and SOFC Integration for a Sustainable Energy Future─A Review and Perspectives

Energy & Fuels, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 14, 2025

Green ammonia emerges as an important candidate for the transition toward sustainable energy solutions to address global imperative carbon neutrality. The current review explores electrochemical synthesis of and its integration into Solid Oxide Fuel Cells (SOFCs) while also challenging traditional method, known substantial consumption considerable footprint. specific advances covered in this article include lithium cycling, electromagnetic fields, plasma technology used ammonia. Innovations have resulted from development efficient single-atom, transition-metal- alloy-based bismuth-based catalysts. In background, paper analyzes advancements made application within SOFCs, emphasizing advancement nickel-based catalysts decomposition technologies that improve both efficiency durability these systems operational settings. This presents a compelling perspective on their potential critical challenges storage, emissions reduction, low-carbon future.

Language: Английский

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Ab Initio Study of a Tandem PdCu Catalyst Supported on Carbon Nitride Nanosheets for Nitrate-to-Ammonia Electrochemical Reduction

ACS Applied Nano Materials, Journal Year: 2025, Volume and Issue: 8(4), P. 1709 - 1717

Published: Jan. 15, 2025

Electrochemical conversion of nitrate offers an efficient approach to mitigate pollution and ammonia synthesis but is still challenged by the slow kinetics selectivity issues active sites. Herein, performing density functional theory (DFT) calculations, we report a double-atom catalyst PdCu–C7N6 incorporating Pd Cu together embedded in C7N6 frameworks, which not only shows outstanding catalytic performance with low limiting potential 0.36 V, also can effectively inhibit competing hydrogen evolution reactions. The high NO3RR activity on well explained polarizable bond length as asymmetric charge distribution Pd–Cu dual This DFT work opens avenue for developing highly multicomponent electrocatalysts.

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

Published: Jan. 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.

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

Published: Feb. 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.

Language: Английский

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

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: March 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

Language: Английский

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

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 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.

Language: Английский

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