Video Experimental Relacionado

Updated: Jan 8, 2026

Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics

Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics

Published on: April 12, 2019

Catalizadores Moleculares para la Reacción de Evolución de Hidrógeno: Un Estudio de Primeros Principios

Samuel Lemay¹, Félix Paradis¹, Mihaela Cibian¹

¹Institut de Recherche Sur l'hydrogène, Université du Québec à Trois-Rivières, Trois-Rivières, C.P. 500 G8z 4m3, Canada.

|December 22, 2025

Abstract:

Molecular catalysts can be used in solution to promote the hydrogen evolution reaction (HER) through electrolysis and photocatalysis. We study the HER from first-principles for four different molecular catalysts, each composed of a transition metal atom and two organic ligands: Co-(bpy)₂, Co-(PyDAT)₂, Ni-(PyDAT)₂, and Cu-(PyDAT)₂. By computing the Gibbs free energy from density functional theory (DFT) at every step of the HER, we identify the protonation sites and the most favorable catalytic pathway on the different catalysts. We compare the efficiency of the different catalysts from their energetic span and from their potential-pH diagrams, showing the operating conditions that make the HER spontaneous. We find that both the nickel- and copper-based systems offer a viable alternative for HER molecular catalysts free of precious metals.

Palabras clave:

catalizadores moleculares reacción de evolución de hidrógeno energía sostenible cálculos de primeros principios níquel cobre catalizadores libres de metales preciosos

Más Videos Relacionados

Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions

Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions

Published on: October 5, 2019

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

Catalysis

Catalysis

The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.

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...

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...

Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation

Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation

Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...

Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation

Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation

Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.

Hydrogen Bonds

Hydrogen Bonds

Hydrogen bonds are weak attractions between atoms that have formed other chemical bonds. One of these atoms is electronegative, like oxygen, and has a partial negative charge. The other is a hydrogen atom that has bonded with another electronegative atom and has a partial positive charge.
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared....