Enhancing hot electron collection with nanotube-based three-dimensional catalytic nanodiode under hydrogen oxidation.

A novel three-dimensional catalytic nanodiode composed of a Pt thin film on TiO2 nanotubes was designed for the efficient detection of the flux of hot electrons, or chemicurrent, under hydrogen oxidation. We verify a significant increase in the chemicurrent from the fast transport of electrons across the ordered supporting oxide layer. This study demonstrates the direct detection of hot electrons on well-ordered TiO2 nanotubes during the catalytic reaction.