Metal containing nanoclusters in zeolites

The molecular-sized void space of the zeolitic micropores is perfect matrices to encapsulate and stabilize multicomponent and multifunctional complexes that can be used as active sites for a wide range of important catalytic transformations. In this article, we discuss and analyze the key developments of the last decade in the catalytic...

CO2 hydrogenation to methanol over Cd4/TiO2 catalyst: Insight into multifunctional interface

Supported metal catalysts have shown to be efficient for CO ₂ conversion due to their multifunctionality and high stability. Herein, we have combined density functional theory calculations with microkinetic modeling to investigate the catalytic reaction mechanisms of CO ₂ hydrogenation to CH ₃OH over a...

Solvent-Assisted Ketone Reduction by a Homogeneous Mn Catalyst

The choice of a solvent and the reaction conditions often defines the overall behavior of a homogeneous catalytic system by affecting the preferred reaction mechanism and thus the activity and selectivity of the catalytic process. Here, we explore the role of solvation in the mechanism of ketone reduction using a model representative of a...

Unraveling the Nature of Extraframework Catalytic Ensembles in Zeolites: Flexibility and Dynamics of the Copper-Oxo Trimers in Mordenite

Extraframework cations define the chemical versatility of zeolite catalysts. Addressing their structural complexity and dynamic behavior represents one of the main fundamental challenges in the field. Herein, we present a computational approach for the identification and analysis of the accessible pool of intrazeolite extraframework complexes...

Gold and silver catalyzed reductive amination of aromatic carboxylic acids to benzylic amines

The reductive amination of benzoic acid and its derivatives would be an effective addition to current synthesis methods for benzylamine. However, with current technology it is very difficult to keep the aromaticity intact when starting from benzoic acid, and salt wastes are often generated in the process. Here, we report a heterogeneous...

Mechanistic investigation of benzene esterification by K₂CO₃/TiO₂: The catalytic role of the multifunctional interface

Potassium carbonate dispersed over a defective TiO₂support (K₂CO₃/TiO₂) is an efficient catalyst for benzene esterification with CO₂and CH₃OH. Density functional theory calculations reveal that this unique catalytic reactivity originates from the cooperation of the Ti<sup>3+<...

Lateral adsorbate interactions inhibit HCOO⁻ while promoting CO selectivity for CO₂ electrocatalysis on silver

Ag is a promising catalyst for the production of carbon monoxide (CO) via the electrochemical reduction of carbon dioxide (CO₂ER). Herein, we study the role of the formate (HCOO⁻) intermediate *OCHO, aiming to resolve the discrepancy between the theoretical understanding and experimental performance of Ag. We show that...

A site-sensitive quasi-in situ strategy to characterize Mo/HZSM-5 during activation

The active sites on the methane dehydroaromatization (MDA) catalyst Mo/HZSM-5 are very hard to characterize, because they are present in various geometries and sizes and only form under reaction conditions with methane at 700 °C. To address these issues an experimental strategy is presented that enables distinguishing different active sites...

Structure and Reactivity of the Mo/ZSM-5 Dehydroaromatization Catalyst: An Operando Computational Study

Mo/ZSM-5 is one of the most studied and efficient catalysts for the dehydroaromatization of methane (MDA), but the mechanism of its operation remains controversial. Here, we combine an ab initio thermodynamic analysis with a comprehensive mechanistic density functional theory study to address Mo-speciation in the zeolite and identify the...

Breaking Linear Scaling Relationships with Secondary Interactions in Confined Space: A Case Study of Methane Oxidation by Fe/ZSM-5 Zeolite

Linear energy scaling laws connect the kinetic and thermodynamic parameters of key elementary steps for heterogeneously catalyzed reactions over defined active sites on open surfaces. Such scaling laws provide a framework for a rapid computational activity screening of families of catalysts, but they also effectively impose a fundamental...

Isolated fe sites in metal organic frameworks catalyze the direct conversion of methane to methanol

Hybrid materials bearing organic and inorganic motifs have been extensively discussed as playgrounds for the implementation of atomically resolved inorganic sites within a confined environment, with an exciting similarity to enzymes. Here, we present the successful design of a site-isolated mixed-metal metal organic framework (MOF) that...

The Nature and Catalytic Function of Cation Sites in Zeolites: a Computational Perspective

Zeolites have a broad spectrum of applications as robust microporous catalysts for various chemical transformations. The reactivity of zeolite catalysts can be tailored by introducing heteroatoms either into the framework or at the extraframework positions that gives rise to the formation of versatile Brønsted acid, Lewis acid and redox...

Mechanistic Complexity of Methane Oxidation with H₂O₂ by Single-Site Fe/ZSM-5 Catalyst

Periodic density functional theory (DFT) calculations were carried out to investigate the mechanism of methane oxidation with H₂O₂ over the defined Fe sites in Fe/ZSM-5 zeolite. The initial Fe site is modeled as a [(H₂O)₂-Fe(III)-(μO)₂-Fe(III)-(H₂O)₂]²⁺...

Unraveling reaction networks behind the catalytic oxidation of methane with H₂O₂ over a mixed-metal MIL-53(Al,Fe) MOF catalyst

Reaction paths underlying the catalytic oxidation of methane with H₂O₂ over an Fe containing MIL-53(Al) metal-organic framework were studied by periodic DFT calculations. Not only the activation of methane, but the full reaction network was considered, which includes the formation of the active site, the overoxidation of...

Electronic Structure of the [Cu₃(μ-O)₃]²⁺ Cluster in Mordenite Zeolite and Its Effects on the Methane to Methanol Oxidation

Identifying Cu-exchanged zeolites able to activate C-H bonds and selectively convert methane to methanol is a challenge in the field of biomimetic heterogeneous catalysis. Recent experiments point to the importance of trinuclear [Cu₃(μ-O)₃]²⁺ complexes inside the micropores of mordenite (MOR) zeolite for...