1 research outputs found
Nanofabricated Catalyst Particles for the Investigation of Catalytic Carbon Oxidation by Oxygen Spillover
The catalytic oxidation of carbon by molecular oxygen was studied
using C/Pt, Pt/C, Pt/Al<sub>2</sub>O<sub>3</sub>/C, Pt/CeO<sub>2</sub>/C, Al<sub>2</sub>O<sub>3</sub>/C, and CeO<sub>2</sub>/C model samples
prepared by hole-mask colloidal lithography. By this technique, the
degree of contact between platinum and carbon was controlled with
high precision. The oxidation of carbon was monitored using atomic
force microscopy and scanning electron microscopy. The results show
that Pt in direct contact with carbon catalyzes the oxidation of carbon
by spillover of dissociated oxygen from Pt to carbon. By physically
separating Pt and carbon with a 10 nm thin spacer layer of Al<sub>2</sub>O<sub>3</sub>, the oxygen spillover was entirely blocked.
However, through a corresponding spacer layer of CeO<sub>2</sub>,
carbon oxidation was still observed, either by oxygen spillover from
Pt to carbon or directly dissociated on the ceria, although at a slower
rate compared to the case with no spacer layer between Pt and carbon