Theoretical insight into the selectivities of copper-catalyzing heterogeneous reduction of carbon dioxide

Understanding and Tuning the Effects of H2O on Catalytic CO and CO2 Hydrogenation

Catalytic COx (CO and CO2) hydrogenation to valued chemicals is one of the promising approaches to address challenges in energy, environment, and climate change. H2O is an inevitable side product in these reactions, where its existence and effect are often ignored. In fact, H2O significantly influences the catalytic active centers, reaction mechanism, and catalytic performance, preventing us from a definitive and deep understanding on the structure-performance relationship of the authentic catalysts. It is necessary, although challenging, to clarify its effect and provide practical strategies to tune the concentration and distribution of H2O to optimize its influence. In this review, we focus on how H2O in COx hydrogenation induces the structural evolution of catalysts and assists in the catalytic processes, as well as efforts to understand the underlying mechanism. We summarize and discuss some representative tuning strategies for realizing the rapid removal or local enrichment of H2O around the catalysts, along with brief techno-economic analysis and life cycle assessment. These fundamental understandings and strategies are further extended to the reactions of CO and CO2 reduction under an external field (light, electricity, and plasma). We also present suggestions and prospects for deciphering and controlling the effect of H2O in practical applications.

Origin of CO2 as the main carbon source in syngas-to-methanol process over Cu: theoretical evidence from a combined DFT and microkinetic modeling study

A theoretical study combining DFT and microkinetic modeling provides evidence that CO₂ is the main carbon source in methanol synthesis from syngas (CO, CO₂ and H₂) over Cu.

Theoretical understanding of the electrochemical reaction barrier: a kinetic study of CO2 reduction reaction on copper electrodes

The electrochemical reduction of CO₂ is a promising route for converting intermittent renewable energy into storable fuels and useful chemical products.

DFT study of furfural conversion on a Re/Pt bimetallic surface: synergetic effect on the promotion of hydrodeoxygenation

Density functional theory (DFT) calculations of furfural conversion were performed via hydrogenation and hydrodeoxygenation pathways on a bimetallic surface, namely, a thin oxygen-covered Re film on Pt(111). In the most stable adsorption conformation, the furyl ring component adsorbs on the Re edge site and the carbonyl oxygen also plays an important role in the adsorption strength. It was found that, while furfural conversion is kinetically favoured in the hydrogenation route to generate furfuryl alcohol, the hydrodeoxygenation mechanism to generate 2-methylfuran and water is thermodynamically favoured. Our results show that the hydrodeoxygenation product 2-methylfuran is achievable via the hydrogenation of furfural into hydroxyalkyl species, followed by C-OH bond cleavage, and successive hydrogenations of the furyl-CH intermediate. However, the production of 2-methylfuran is prohibited as the oxidised Re surface cannot accept further oxygen deposition, due to the oxygen-related species are difficult to remove in the form of water via hydrogenation. By comparing the results from the Re/Pt system to those on a monometallic flat Pt surface, we were able to demonstrate that incorporation of the oxophilic metals to active metals for hydrogenation could promote the hydrodeoxygenation route by reducing the barrier of C-O bond cleavage.

A DFT study of direct furfural conversion to 2-methylfuran on the Ru/Co3O4 surface

We investigate the direct conversion of furfural to 2-methylfuran on Ru/Co₃O₄ using DFT calculations.

Enhanced formation of >C1 Products in Electroreduction of CO2 by Adding a CO2 Adsorption Component to a Gas-Diffusion Layer-Type Catalytic Electrode

The addition of a CO₂ -adsorption component (substituted imidazolate-based SIM-1 crystals) to a gas-diffusion layer-type catalytic electrode enhances the activity and especially the selectivity towards >C1 carbon chain products (ethanol, acetone, and isopropanol) of a Pt-based electrocatalyst that is not able to form products of CO₂ reduction involving C-C bond formation under conventional (liquid-phase) conditions. This indicates that the increase of the effective CO₂ concentration at the electrode active surface is the factor controlling the formation of >C1 products rather than only the intrinsic properties of the electrocatalyst.

A rational catalyst design of CO oxidation using the bonding contribution equation

A rational design of heterogeneous catalysts is an important yet challenging task.

Formulating the bonding contribution equation in heterogeneous catalysis: a quantitative description between the surface structure and adsorption energy

The relation between the surface structure and adsorption energy of adsorbates is of great importance in heterogeneous catalysis.

Significant enhancement of the selectivity of propylene epoxidation for propylene oxide: a molecular oxygen mechanism

As an attractive and environmentally friendly process for propylene oxide (PO) production, direct epoxidation of propylene (DEP) with molecular oxygen catalyzed by metal-based catalysts such as Ag and Cu has drawn much attention, but remains one of the biggest challenges in chemistry.

Electrochemical behaviour of naked sub-nanometre sized copper clusters and effect of CO2

In size-controlled naked Cu₅ and Cu₂₀ nanoclusters the latter show anodic redox processes occurring at much lower potential with respect to Cu₅, but the latter coordinate effectively CO₂ and allow to reduce CO₂ under cathodic conditions at lower overpotential.

Methanol formation by catalytic hydrogenation of CO2 on a nitrogen doped zinc oxide surface: an evaluative study on the mechanistic pathway by density functional theory

Computational evaluation of reaction pathway for simultaneous activation of CO₂ and water on N doped ZnO surface revealed carbamate mediated methanol formation.