Mechanism of CO2 hydrogenation to methanol on the W-doped Rh(111) surface unveiled by first-principles calculation

Recent Advances in the Reverse Water-Gas Conversion Reaction

The increase in carbon dioxide emissions has significantly impacted human society and the global environment. As carbon dioxide is the most abundant and cheap C1 resource, the conversion and utilization of carbon dioxide have received extensive attention from researchers. Among the many carbon dioxide conversion and utilization methods, the reverse water-gas conversion (RWGS) reaction is considered one of the most effective. This review discusses the research progress made in RWGS with various heterogeneous metal catalyst types, covering topics such as catalyst performance, thermodynamic analysis, kinetics and reaction mechanisms, and catalyst design and preparation, and suggests future research on RWGS heterogeneous catalysts.

Rare Earth Metal Anchored into Nitrogen-Doped Graphene for CO2 Electrocatalytic Reduction to C1 Products

Single-atom catalysts (SACs) are attracting global attention due to their 100% atomic utilization rate and unique properties. Rare-earth-based SACs have shown great potential in the field of electrocatalysis in recent years. In this study, the catalytic performance of four rare earth metals (REMs) anchored into N-graphene for the CO2RR is systematically studied by density functional theory. The calculation results of formation energy show that all REM@N6-G compounds have favorable stability. In addition, the Gibbs free energy calculation results of all possible elementary reactions show that the *OCHO pathway is the optimal hydrogenation pathway for all catalysts, and they have the same potential determining step (*OCHO + e- + H+ → *HCOOH). Meanwhile, the products of the CO2RR on these catalysts are different, and the product on REM@N6-G (REM = La, Pr, and Nd) is CH4, while the product on Ce@N6-G is CH3OH. In particular, Nd@N6-G exhibits the best catalytic activity in this work, with a very low limiting potential of -0.38 V. These results may guide the development of rare-earth-based SACs for CO2RR.

Unraveling the Catalytic Performance of the Nonprecious Metal Single-Atom-Embedded Graphitic s-Triazine-Based C3N4 for CO2 Hydrogenation

Graphitic carbon nitride (g-C₃N₄) is regarded as a promising potent photoelectrocatalyst for CO₂ reduction. Here, extensive first-principles calculations and ab initio molecular dynamics (AIMD) simulations are performed to systematically explore the structural and electronic properties of nonprecious metal single-atom-embedded graphitic s-triazine-based C₃N₄ (M@gt-C₃N₄, M = Mn, Fe, Co, Ni, Cu, and Mo) monolayer materials and their catalytic performances as the single-atom catalysts (SACs) for CO₂ hydrogenation to HCOOH, CO, and CH₃OH. It is found that the atomically dispersed non-noble metal Mn, Fe, Co, and Mo sites anchored on gt-C₃N₄ can efficiently activate both H₂ and CO₂, and their coadsorbed state serves as a precursor to the hydrogenation of CO₂ to different C1 products. Among these SACs (M@gt-C₃N₄, M = Mn, Fe, Co, and Mo), Co@gt-C₃N₄ was predicted to have the best catalytic performance for CO₂ hydrogenation to C1 products, although their mechanistic details are somewhat different. The predicted energy barriers of the rate-determining steps for the conversion of CO₂ into HCOOH, CO, and CH₃OH on Co@gt-C₃N₄ are 0.58, 0.67, and 1.19 eV, respectively. The desorption of products is generally energy-demanding, but it can be facilitated remarkably by the subsequent adsorption of H₂, which regenerates M@gt-C₃N₄ for the next catalytic cycle. The present study demonstrates that the catalytic performance of gt-C₃N₄ can be well regulated by embedding the non-noble metal single atom, and the porous gt-C₃N₄ is nicely suited for the construction of high-performance single-atom catalysts.

Density functional theoretical study of the tungsten-doped In2O3 catalyst for CO2 hydrogenation to methanol

W doping makes CO2 hydrogenation to methanol on In2O3 kinetically more favorable based on DFT calculations.