IFISUR   23398
INSTITUTO DE FISICA DEL SUR
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
DFT study of NO2 reduction by Cu, Ag and Au nanoparticles and the respective (111) surfaces
Autor/es:
PASCUCCI, BRUNO; OTERO, GUADALUPE SOL; BELELLI PATRICIA GABRIELA; ILLAS, FRANCESC; BRANDA, MARÍA MARTA
Lugar:
Granada
Reunión:
Congreso; XXXIX Congreso Internacional de Químicos Teóricos de Expresión Latina (Quitel 2013); 2013
Institución organizadora:
Químicos Teóricos de Expresión Latina
Resumen:
NO2 decomposition to NO + O catalyzed by cubo-octahedral nanoparticles of Cu, Ag and Au has been theoretically studied and the energy profile compared to the corresponding one for extended (111) surfaces. In all cases, adsorption at the on-top sites were found to be preferred with adsorption energy increasing in the order Cu > Ag > Au but for the nanoparticles, the calculated adsorption energy values is always larger than on the respective (111) surface. Note, however, that the nanoparticles exhibit also low coordinated sites which are especially active. Concerning NO and O and the (111) surfaces, the preferred sites are NO on-top and O on hollow. In the case of the Cu(111) surface the NO2 decomposition reaction is slightly endothermic (+0.25 eV) but it is endothermic by +1.2 eV and +1.5 eV on Ag(111) and Au(111), respectively. Interestingly, for Cu19 one finds that NO and O prefer bridge and hollow sites, respectively, and precisely in this case the reaction is slightly exothermic (-0.33 eV) whereas it is endothermic by about +1.8 eV for both Ag19 and Au19 nanoparticles.