Non-noble metal single-atom catalyst of Co1/MXene (Mo2CS2) for CO oxidation

Abstract

MXene is a variety of new two-dimensional (2D) materials with early transition metal carbides, nitrides, and carbonitrides. Quantum chemical studies have been carried out on the geometries, electronic structures, stability and catalytic properties of a non-noble metal single-atom catalyst (SAC) with single Co atom anchored on MXene materials of Mo 2 CS 2. The Co adatom anchored on top of the Mo atom of this MXene is found to be rather stable, and this SAC is appropriate for CO oxidation. The charge transfers from the surface to the adsorbed CO and O 2 play a significant role in the activation of these molecules on Co 1 /Mo 2 CS 2. With this catalyst, the Eley-Rideal (ER), Langmuir-Hinshelwood (LH), and Termolecular Eley-Rideal (TER) mechanisms are explored for CO oxidation. We find that, while all the three mechanisms are feasible at low temperature, Co 1 /Mo 2 CS 2 possesses higher catalytic activity for CO oxidation through the TER mechanism that features an intriguing OC(OO)CO intermediate (IM) adsorbed on Co single atom. The calculated activation energy barriers of the rate-limiting step are 0.67 eV (TER), 0.78 eV (LH) and 0.88 eV (ER), respectively. The present study illustrates that it is promising to develop and design low-cost, non-noble metal SACs using MXene types of 2D materials.

Comprehensive Mechanism of CO2 Electroreduction on Non‐Noble Metal Single‐Atom Catalysts of Mo2CS2‐MXene

“…It is found that the S atom structure of the bridge site will migrate to the hcp site after optimization, for the Mo 2 CS 2 of the hcp site has the lowest total energy and the most stable structure, which is consistent with the calculation results of Talib et al. [59] . In order to avoid the interaction between adjacent CO 2 caused by periodicity, a 3×3 Mo 2 CS 2 supercell is used in this article to anchor TM atoms.…”

Late Transition Metal Doped MXenes Showing Superb Bifunctional Electrocatalytic Activities for Water Splitting via Distinctive Mechanistic Pathways

“…Among many other competing 2D materials, MXene sheets with large active sites, highly hydrophilic surface, good charge transfer kinetics, high electrical conductivity, and good structural stability provide polished qualities to become efficient catalysts. [ 42–45 ] MXenes are the newly emerging family of 2D TM carbides and nitrides with the general formula M n +1 X n T m ( n = 1–4), where M represents early TMs, X = C and/or N element and T represents the surface functional groups such as OH, O and, F. Recently, the family of MXenes has been expanded to include the ordered double‐TM carbides M 2 M ′ C 2 and M 2 M 2 ′ C 3 .…”

Theoretical studies of MXene-supported single-atom catalysts: Os1/Ti2CS2 for low-temperature CO oxidation

“…Recently, MXenes composed with transition metal carbides, carbonitrides and nitrides [68], as a new type of multiatomic-layer 2D nanomaterial, have received a lot of attention both theoretically and experimentally because of their versatile applications in energy storage, catalysis, sensors, flexible functional materials, etc. [32,[69][70][71][72][73][74][75][76]. The general formula of MXene is denoted as M n+1 X n T x (n = 1-4) [68,[77][78][79], where M is an early transition metal (Ti, V, Cr, Nb, Mo, etc.…”