Tölvureikningar á rafefnafræðilegri afoxun CO2 í vistvænt eldsneyti með kopar nanóögnum

Abstract

Calculations were done for electrochemical CO2 reduction to both methanol and methane formation on three copper nanoparticles that differ by size and configuration; 55 atom particle (Cu55) and two different 78 atom particles (Cu78-type1 and Cu78-type2) along with a Cu147 NP. The calculations predict the lowest free energy pathway along with their onset potentials, which is the applied potential needed to start the reactions. The calculations were done using density functional theory using both the BEEF-vdW and the RPBE density functionals. The onset potentials were compared with previous results from an extended Cu(111) surface. We predict Cu55, Cu78-type1, Cu78-type2 and Cu147 NPs to have onset potentials of 0.86 V, 0.78 V,0.82 V and 0.87 V respectively, which is very close to the onset potential of the Cu(111) surface of 0.81 V. Therefore, these results indicate that the CO2 onset potential for the nanoparticles considered in this work do not differ much from the flat surface.