ИСТИНА

A wide interest towards the catalytic activity of flat clusters of late transition and noble metals at surfaces of oxides, nitrides, and carbides has been stimulated owing mainly to a variety of possible important chemical processes. A rare case of formation of flat Pd clusters (with a diameter of ~1 nm) from single Pd atoms in H2 atmosphere was found on anatase surfaces above 375°C and at small Pd loadings [1]. It is accompanied by an increase (per Pd atom) of a reverse water−gas shift (rWGS) reaction thus showing a higher reaction rate at flat Pd clusters versus at single Pd atoms [1]. Such specific growth of the activity was not observed for other metals (Pt [2]) and other supports [1] while small Pt clusters were observed compared to Pd monolayers on (101) anatase [1]. 2D slab models of Me monolayers, Me = Pt and Pd, were optimized at both (101) and (001) facets of anatase, which could serve as precursor of small flat clusters. The reactivity of single atoms, mono- and bi-layers has been studied for CO2 hydrogenation, and H2 and H2O dissociation which are important for both reverse and direct water−gas shift reactions. Ab initio molecular dynamics (AIMD) has been applied to check the stability of Me monolayers at picosecond scale. The computations were carried out using the equipment of the shared research facilities of HPC computing resources at Lomonosov Moscow State University and the resources at the Joint Supercomputer Center of the Russian Academy of Sciences (JSCC RAS), as well as the Plateforme Technologique de Calcul Intensif (P.T.C.I.; http://www.ptci.unamur.be), located at the University of Namur, which is part of the Consortium des Equipements de Calcul Intensif (C.E.C.I., supported by the F.R.S.-FNRS, Belgium; http://www.ceci-hpc.be). 1. Linxiao Chen et al., J Am Chem Soc. 2023, 145, 10847-10860. doi: 10.1021/jacs.3c02326 2. Linxiao Chen et al., JACS Au 2021, 1, 977−986. doi:10.1021/jacsau.1c00111