Hot Electron Transport on Three-Dimensional Pt/Mesoporous TiO 2 Schottky Nanodiodes

© 2019 American Chemical Society. We present the design of a three-dimensional Pt/mesoporous TiO 2 Schottky nanodiode that can capture hot electrons more effectively, compared with a typical two-dimensional Schottky diode. Both chemically induced and photon-induced hot electrons were measured on the three-dimensional Pt/mesoporous TiO 2 Schottky nanodiode. An increase in the number of interfacial sites between the platinum and support oxide affects the collection of hot electrons generated by both the catalytic reaction and light injection. We show that hot electrons flowing 2.5 times higher are detected as the current in the mesoporous system, compared with typical two-dimensional nanodiode systems that have a planar Schottky junction. Identical trends for the chemicurrent and photocurrent in the mesoporous system demonstrate that the enhanced hot electrons are attributed to the larger interface area between the metal and the mesoporous TiO 2 support fabricated by the anodization process. This three-dimensional Schottky nanodiode can provide insights into hot electron generation on a practical catalytic devic

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. © The Royal Society of Chemistr

Elucidating the mechanism of the considerable mechanical stiffening of DNA induced by the couple Zn2+/Calix[4]arene-1,3-O-diphosphorous acid

Abstract The couple Calix[4]arene-1,3-O-diphosphorous acid (C4diP) and zinc ions (Zn2+) acts as a synergistic DNA binder. Silicon NanoTweezer (SNT) measurements show an increase in the mechanical stiffness of DNA bundles by a factor of >150, at Zn2+ to C4diP ratios above 8, as compared to Zinc alone whereas C4diP alone decreases the stiffness of DNA. Electroanalytical measurements using 3D printed devices demonstrate a progression of events in the assembly of C4diP on DNA promoted by zinc ions. A mechanism at the molecular level can be deduced in which C4diP initially coordinates to DNA by phosphate-phosphate hydrogen bonds or in the presence of Zn2+ by Zn2+ bridging coordination of the phosphate groups. Then, at high ratios of Zn2+ to C4diP, interdigitated dimerization of C4diP is followed by cross coordination of DNA strands through Zn2+/C4diP inter-strand interaction. The sum of these interactions leads to strong stiffening of the DNA bundles and increased inter-strand binding