Interaction of SO2 with Cu/TiC(0 0 1) and Au/TiC(0 0 1): Toward a new family of DeSOx catalysts

Experiments carried out under well-controlled conditions and density functional theory (DFT)-based calculations evidence that Cu and Au nanoparticles supported on a TiC(0 0 1) surface are quite active for the dissociation of the SO2 molecule. The Cu/TiC(0 0 1) and Au/TiC(0 0 1) systems cleave both S–O bonds of SO2 at a temperature of 150 K, displaying a reactivity much larger than that of TiC(0 0 1) or extended surfaces of bulk copper and gold. The origin of the high activity of the Cu/TiC(0 0 1) and Au/TiC(0 0 1) systems lies on the interaction between the C atoms of the substrate and the metal atoms of the supported particle, which results in a large polarization of its electron density. Experiments and theory consistently indicate that the Cu/TiC system is more active toward SO2 dissociation than the Au/TiC system. This type of systems may provide alternative and efficient DeSOx catalysts.