Effective Nitrate Electroconversion to Ammonia Using an Entangled Co3O4/Graphene Nanoribbon Catalyst DOI Creative Commons
Marciélli K. R. Souza, Eduardo S. F. Cardoso, L.M.C. Pinto

et al.

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 17(1), P. 1295 - 1310

Published: Dec. 27, 2024

There has been huge interest among chemical scientists in the electrochemical reduction of nitrate (NO3-) to ammonia (NH4+) due useful application NH4+ nitrogen fertilizers and fuel. To conduct such a complex reaction, which involves eight electrons protons, one needs develop high-performance (and stable) electrocatalysts that favor formation reaction intermediates are selective toward production. In present study, we developed applied Co3O4/graphene nanoribbon (GNR) with excellent properties for effective NO3- NH4+, where yield rate 42.11 mg h-1 mgcat-1, FE 98.7%, conversion efficiency 14.71%, selectivity 100% were obtained, only 37.5 μg cm-2 catalysts (for best catalyst ─Co3O4(Cowt %55)GNR, 20.6 Co was applied), confirmed by loadings ranging from 19-150 cm-2. The highly satisfactory results obtained proposed favored high average values electrochemically active surface area (ECSA) low Rct values, along presence several planes Co3O4 entangled GNR occurrence kind "(Co3(Co(CN)6)2(H2O)12)1.333 complex" structure on surface, addition migration cell cathodic branch anodic branch, experiment conducted using H-cell separated Nafion 117 membrane. situ FTIR Raman spectroscopy helped identify adsorbed intermediates, namely, NO3-, NO2-, NO, NH2OH, final product compatible electroreduction mechanism. Density Functional Theory (DFT) calculations confirm Co3O4(Cowt %55)GNR exhibited better performance terms comparison %75), considering identified rate-determining step (RDS) observed transition *NO *NHO (0.43 eV).

Language: Английский

From Proximity to Energetics: Unveiling the Hidden Compass of Hydrogen Evolution Reaction DOI
Arun Karmakar,

Mahendiran Durairaj,

Ragunath Madhu

et al.

ACS Materials Letters, Journal Year: 2024, Volume and Issue: 6(7), P. 3050 - 3062

Published: June 14, 2024

The Volmer–Tafel (VT) and Volmer–Heyrovsky (VH) mechanisms were believed to be determined solely by the proximity of adsorbed hydrogen atoms on metallic surfaces for evolution reaction (HER). However, recent investigations challenge this notion, particularly with catalysts such as Au Ag, where VH pathways are observed despite close atom distance. This study investigates influence free energy adsorption (ΔGH*) active site density HER pathways, incorporating consideration rate-determining step (RDS). Contrary previous assumptions, it is found that ΔGH* plays a pivotal role, VT favored when approaches zero, while occurs in other cases, irrespective density. inclusive analysis, integrating both thermodynamic energetic considerations experimental theoretical support, sheds new light mechanistic intricacies HER, challenging conventional paradigms providing insights crucial catalyst design.

Language: Английский

Citations

8
Unlocking the role of byproducts in reactive laser ablation in liquids: A pathway to dual-function Au-Ti nanostructures DOI
K Kassa, Sabrin Abdallah, Ondřej Havelka

et al.

Applied Surface Science, Journal Year: 2025, Volume and Issue: unknown, P. 162713 - 162713

Published: Feb. 1, 2025

Language: Английский

Citations

0
A Tetranuclear NiII4O4 Cubane Molecular Complex as an Efficient Electrocatalyst for Oxygen Evolution Reaction: From Synthesis to Mechanistic Insights DOI

Joshi Ankitkumar Bharatbhai,

Soumalya Roy, Atanu Dey

et al.

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

Published: May 12, 2025

Abstract The oxygen evolution reaction (OER) is integral to electrochemical energy systems; however, its intrinsic sluggish kinetics necessitate the design of high‐performance electrocatalysts minimize overpotential, enhance durability, and optimize efficiency. Significant efforts have been dedicated developing OER catalysts based on earth‐abundant transition‐metal complexes. Here, efficacy a tetranuclear cubane‐cored Ni(II) complex, [Ni₄(LH)₄(MeOH)]·CHCl₃ ( 1 ), in demonstrated. complex synthesized using tetradentate Schiff‐base ligand, [2‐{( E )‐(2‐hydroxyphenylimino)methyl)‐6‐(hydroxymethyl)‐4‐methylphenol}], characterized by single‐crystal X‐ray diffraction. redox properties are evaluated cyclic voltammetry solid state, which emphasize quasireversible oxidation state metal center. immobilized activated carbon cloth CC referred as CC‐1 , demonstrates efficient catalysis, subsequently activating form Ni(O)OH catalyst. postreaction analysis including UV–vis, FTIR, scanning electron microscopy–energy‐dispersive spectroscopy, photoelectron spectroscopy confirm stability molecular . results demonstrate catalysis with low overpotential 330 mV versus reversible hydrogen electrode Tafel slope 64 dec −1 confirming an effective catalyst alkaline medium deep understanding core mechanisms.

Language: Английский

Citations

0
Theoretical Understanding of the Structure–Property Relationship of Oxygen-Doped Gallium Selenide as an Efficient Photocatalyst for Oxygen Evolution Reaction DOI
Ephrem G. Demissie, Chi‐Kit Siu

The Journal of Physical Chemistry C, Journal Year: 2024, Volume and Issue: unknown

Published: June 10, 2024

A single-layer of GaSe is widely regarded as one the most promising photocatalysts for a solar-driven water-splitting reaction. However, its catalytic performance limited by high onset potential oxygen evolution reaction (OER). Achieving ideal adsorption strength each intermediate (HO*, O*, and HOO*) involved in OER process simultaneously via surface modification two-dimensional (2D) materials significant challenge. In this study, effects partial replacement Se atoms with O on activity resulting 2D GaSe1–xOx toward have been systematically examined using density functional theory calculations. Our theoretical results revealed that manipulating atomic configuration dopants largely improves GaSe1–xOx. When O-dopants are separated −Ga–Se–Ga– unit, strong O* intermediate. On contrary, when −Ga– unit bonded three O-dopants, O-saturated Ga atom serves best site to initiate exhibits predicted overpotential 0.38 V, which comparable values many state-of-the-art precise-metal-based catalysts.

Language: Английский

Citations

0
Quantitative study of oxygen evolution reaction using LiNi0.5Mn1.5O4 thin-film electrodes DOI Creative Commons
Kentaro Hatagami, Kazunori Nishio, Ryota Shimizu

et al.

Journal of Applied Physics, Journal Year: 2024, Volume and Issue: 135(23)

Published: June 17, 2024

The development of water electrolysis catalysts that accelerate the oxygen evolution reaction (OER) is a crucial challenge. Ni-based oxides are promising OER catalysts; however, quantitative studies remain unexplored. In this study, we quantitatively evaluated activity LiNi0.5Mn1.5O4 as thin-film electrode catalyst. thin film fabricated using sputtering method exhibited current density 6.6 and ∼2.6 mAcm−2 for geometric estimated areas, respectively, at 1.78 V vs. reversible hydrogen electrode. X-ray photoelectron spectroscopy indicated presence Ni3+ in as-grown post-OER films. These results suggest plays key role LiNi0.5Mn1.5O4.

Language: Английский

Citations

0
Effective Nitrate Electroconversion to Ammonia Using an Entangled Co3O4/Graphene Nanoribbon Catalyst DOI Creative Commons
Marciélli K. R. Souza, Eduardo S. F. Cardoso, L.M.C. Pinto

et al.

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 17(1), P. 1295 - 1310

Published: Dec. 27, 2024

There has been huge interest among chemical scientists in the electrochemical reduction of nitrate (NO3-) to ammonia (NH4+) due useful application NH4+ nitrogen fertilizers and fuel. To conduct such a complex reaction, which involves eight electrons protons, one needs develop high-performance (and stable) electrocatalysts that favor formation reaction intermediates are selective toward production. In present study, we developed applied Co3O4/graphene nanoribbon (GNR) with excellent properties for effective NO3- NH4+, where yield rate 42.11 mg h-1 mgcat-1, FE 98.7%, conversion efficiency 14.71%, selectivity 100% were obtained, only 37.5 μg cm-2 catalysts (for best catalyst ─Co3O4(Cowt %55)GNR, 20.6 Co was applied), confirmed by loadings ranging from 19-150 cm-2. The highly satisfactory results obtained proposed favored high average values electrochemically active surface area (ECSA) low Rct values, along presence several planes Co3O4 entangled GNR occurrence kind "(Co3(Co(CN)6)2(H2O)12)1.333 complex" structure on surface, addition migration cell cathodic branch anodic branch, experiment conducted using H-cell separated Nafion 117 membrane. situ FTIR Raman spectroscopy helped identify adsorbed intermediates, namely, NO3-, NO2-, NO, NH2OH, final product compatible electroreduction mechanism. Density Functional Theory (DFT) calculations confirm Co3O4(Cowt %55)GNR exhibited better performance terms comparison %75), considering identified rate-determining step (RDS) observed transition *NO *NHO (0.43 eV).

Language: Английский

Citations

0