Capture of CO2 and its conversion into organic feedstocks are increasingly needed as society moves towards a renewable energy economy. Here, a hydride‐assisted selective reduction pathway is proposed for the conversion of CO2 to formic acid (FA) over SnO2 monomers and dimers. Our density functional theory calculations infer a strong chemisorption of CO2 on SnO2 clusters forming a carbonate structure, whereas heterolytic cleavage of H2 provides a new pathway for the selective reduction of CO2 to formic acid at low overpotential. Among the two investigated pathways for reduction of CO2 to HCOOH, the hydride pinning pathway is found promising with a unique selectivity for HCOOH. The negatively‐charged hydride forms on the cluster during the dissociation of H2 and facilitates the formation of a formate intermediate, which determines the selectivity for FA over the alternative CO and H2 evolution reaction. It is confirmed that SnO2 clusters exhibit a different catalytic behaviour from their surface equivalents, thus offering promise for future work investigating the reduction of CO2 to FA via a hydride pinning pathway at low overpotential and CO2 capturing.

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Escalation of nitrogen monoxide (NO) concentration into the atmosphere has caused severe environmental problems. So, it is important to prepare or design a suitable catalytic system to understand the oxidation of NO into NO2 at the molecular level. In this regard, a comprehensive theoretical investigation of the catalytic oxidation of NO on anionic bimetallic dimers [Au–M]− (M = Pd, Pt) has been considered here using the density functional theory method at the M06L functional along with def2TZVP basis set. To refine the energies and electronic properties of all species, single-point energy calculations are further performed with the CCSD­(T) method using the same basis set. The adsorption of NO and O2 on bimetallic dimers is studied, and binding energy has been calculated to understand the stability of the adsorbed species. Our calculations show that M sites are found to be the preferred site for adsorption rather than Au site. Further, full catalytic reaction pathways using the Langmuir–Hinshelwood mechanism are investigated in which two NO molecules are converted into two NO2 molecules in the presence of an activated O2 molecule. Moreover, an energetic span model has justified that conversion on [Au–Pd]− catalyst possesses a lower apparent activation energy than that on [Au–Pt]− which makes [Au–Pd]− a more efficient catalyst toward the catalytic conversion of NO into NO2. Thus, the present study will convey an understanding of the mechanism of NO oxidation at the molecular level as well as designing better catalysts for future prospects.

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