Mechanistic Details of Catalytic Hydrogenation of CO 2 to Useful Chemicals Using SnO 2 Clusters

Mitigating CO 2 and its conversion into valuable chemicals are obligatory as continuous emission of CO 2 becomes a threat to the sudden global climate change and hence living beings. To overcome such a problem, nanoscience and nanotechnology took frontiers in scientific research. Generally, clusters in nano and subnanometer regions exhibit different physical and chemical properties than their bulk due to the quantum size effect, which makes their study interesting. Herein, our focus is on the theoretical determination of global minimum structures of tin dioxide using the genetic algorithm technique implemented in the knowledge-led master code (KLMC) program. Different physical and electronic properties are discussed. Further, these clusters are used to explore the reaction pathways for the hydrogenation of CO 2 to formic acid (FA). The adsorption of CO 2 and dissociation of H 2 open new ways to capture CO 2 and selective conversion of CO 2 to HCOOH, respectively. The new hydride pinning pathway turned out to be an efficient pathway for the selective reduction of CO 2 to HCOOH at lower overpotential. This chapter also provides an insight into the experimental field to synthesize and characterize small-sized SnO 2 nanoparticles within the range of quantum sizes effect.