Formic Acid Synthesis by CO2 Hydrogenation over Single-Atom Catalysts Based on Ru and Cu Embedded in Graphene Academic Article uri icon


  • AbstractAt variance with conventional heterogeneous catalysts, where only a small number of transition or noble metal atoms at surfaces play the role of active sites, in the singleatom catalysts (SAC) each metal atom is involved in the catalytic process. Starting from isolated Ru and Cu atoms embedded on defects in graphene, denoted as RudG and CudG, we apply density functional theory (DFT) to examine utilizing these structures to catalyze the conversion of CO2 into the formic acid (FA). Our atomistic modeling of this reaction, highly relevant for reducing the CO2 level in the atmosphere, includes three different reaction pathways. The first relies on a direct hydrogenation of CO2 with protons from the H2 molecule. Due to energy barriers higher than 35kcal/mol on both RudG and CudG, this reaction path does not represent a favorable route for FA synthesis. The other two reaction mechanisms start with the dissociative adsorption of H2 and then proceed via completely different paths. At RudG the CO2 hydrogenation occurs with the H atoms from the dissociated H2, while the CudG favors the proton transfer from an additional H2, coadsorbed with CO2 on hydrogenated SAC. Since we find that these pathways were accompanied with the activation energies smaller than 20kcal/mol, our DFT study indicates that the Ru adatoms embedded into the defected graphene are promising candidates for designing a SAC enabling an efficient conversion of CO2 to FA. Since adsorbed H species markedly decrease Cu binding at the vacancy sites, the CudG is considerably less robust catalyst than RudG.

published proceedings


altmetric score

  • 3

author list (cited authors)

  • Sredojevic, D. N., Sljivancanin, Z., Brothers, E. N., & Belic, M. R.

citation count

  • 30

complete list of authors

  • Sredojevic, Dusan N||Sljivancanin, Zeljko||Brothers, Edward N||Belic, Milivoj R

publication date

  • March 2018