Low Energy Indium or Gallium Ion Implantations to SiO₂Thin Films for Development of Novel Catalysts

Abstract

In an earlier paper [S. Yoshimura et al., Appl. Surf. Sci. 257, 192 (2010)], it has been demonstrated that indium (In) implanted silicon dioxide (SiO2) thin films catalyze a reaction of benzhydrol with acetylacetone. In this study, it is found that the threshold In ion incident energy for manifestation of the catalytic effect exists between 400 and 470 eV. Furthermore, a technique to implant gallium (Ga) to SiO2 films has been developed with highly controlled doses and injection energies for the formation of thin films that promote Ga catalysts. The efficiency of catalytic reactions by Ga implanted SiO2 thin films is yet to be improved. Unlike In implanted SiO2, the reason why no significant reaction was observed in the case of Ga implanted SiO2 films examined in this study seems that the Ga ion energy was so low that deposited surface Ga atoms should lack interactions with Si atoms for the manifestation of catalytic reaction.