Video Experimental Relacionado

Updated: May 30, 2025

Hydrogen Production and Utilization in a Membrane Reactor

Hydrogen Production and Utilization in a Membrane Reactor

Published on: March 10, 2023

Las moléculas de CO-P dispersadas atómicamente mediante exfoliación térmica directa para la electrosíntesis de

Zheng Zhou¹, Yixin Su^2,3, Hao Tan⁴

¹Research Institute of Frontier Science, Southwest Jiaotong University, No. 111 Section one of North Second Ring Road, Chengdu 610031, China.

Journal of the American Chemical Society

|January 25, 2025

Resumen

El fosfuro de cobalto atomicamente disperso (CoP4) en las nanohojas de carbono aumenta el rendimiento del electrolizador de membrana de intercambio aniónico. Este nuevo electrocatalizador permite una evolución eficiente del hidrógeno alcalino y un funcionamiento estable, allanando el camino para la comercialización.

Área de la Ciencia:

La electroquímica
Ciencias de los materiales
Catálisis

Sus antecedentes:

La comercialización de los electrolizadores de membrana de intercambio aniónico (AEM) se ve obstaculizada por la falta de cátodos activos y estables en las soluciones alcalinas.
El desarrollo de electrocatalizadores eficientes es crucial para el avance de las tecnologías de producción de hidrógeno.

Objetivo del estudio:

Sintetizar y caracterizar un nuevo electrocatalizador para la reacción de evolución de hidrógeno mejorada (HER) en medios alcalinos.
Evaluar el rendimiento del nuevo catalizador en los electrolizadores AEM.

Principales métodos:

Síntesis de fracciones de CoP4 dispersadas atómicamente en nanohojas de carbono ultrafinas (CoP4-SSC) mediante exfoliación por fosfidación.
Elucidación de la formación de la fracción Co-P mediante espectroscopia de absorción de rayos X (XAS) y cálculos teóricos.
Evaluación electroquímica de la CoP4-SSC para HER y en electrolizadores AEM.

Principales resultados:

CoP4-SSC demostró una alta actividad para el HER alcalino con un bajo sobrepotencial (52 mV a 10 mA cm−2) y una alta frecuencia de rotación (23,83 s−1).
Un electrolizador AEM utilizando CoP4-SSC alcanzó 1 A cm-2 a 1,94 V y mostró una degradación insignificante durante 500 horas.
Las caracterizaciones de Operando y los cálculos de DFT revelaron una nanointerfaz [P-H··H2O-Co] que facilita la disociación del agua a través de la vía Volmer-Heyrovsky.

Conclusiones:

Las fracciones de CoP4 dispersadas atómicamente en nanohojas de carbono representan un electrocatalisador altamente activo y estable para el HER alcalino.
El catalizador desarrollado mejora significativamente el rendimiento del electrolizador AEM, abordando un desafío clave en la comercialización.
La comprensión del mecanismo de interfaz proporciona ideas para el diseño de futuros electrocatalizadores avanzados.

Más Videos Relacionados

Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production

Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production

Published on: December 6, 2021

A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions

A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions

Published on: August 17, 2016

Videos de Conceptos Relacionados

Reduction of Alkenes: Catalytic Hydrogenation

Reduction of Alkenes: Catalytic Hydrogenation

Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...

Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction

Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction

The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...

Thermal and Photochemical Electrocyclic Reactions: Overview

Thermal and Photochemical Electrocyclic Reactions: Overview

Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.

Acid Halides to Alcohols: LiAlH4 Reduction

Acid Halides to Alcohols: LiAlH₄ Reduction

Acid halides are reduced to alcohols in the presence of a strong reducing agent like lithium aluminum hydride.
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...

Amines to Alkenes: Cope Elimination

Amines to Alkenes: Cope Elimination

Cope elimination reaction involves the conversion of tertiary amines to alkene using hydrogen peroxide under thermal conditions, as depicted in figure 1.