Abstract
We used high-quality ZnO nanostructures/graphene substrates for understanding the mechanisms of charge transfer (CT) that take place under nonplasmonic conditions. As the optimal conditions for CT processes are found, we studied the range of CT normal to the ZnO surface that is coated with nanoscale HfO2 layers with different thicknesses. We could observe that CT decays over a few nanometers. In addition, we also observed a unique oscillation of the SERS intensity in the atomically thin oxide layers, which reflects the quantum tunneling effects of CT electrons across the oxide layers. To the best of our knowledge, this is the first direct observation of SERS-active charge transport and measurement of a CT span with atomic-scale accuracy.
| Original language | English |
|---|---|
| Pages (from-to) | 45-49 |
| Number of pages | 5 |
| Journal | Nanoscale |
| Volume | 11 |
| Issue number | 1 |
| DOIs | |
| State | Published - 7 Jan 2019 |
Bibliographical note
Funding Information:This work was supported by the Basic Science Research Program (NRF-2016R1D1A1B01009032 and NRF-2018R1A6A1A03025340) through the National Research Foundation of Korea (NRF). This work was also supported by the Global Research Laboratory Program (2015K1A1A2033332) through the NRF funded by the Ministry of Science, ICT, and Future Planning.
Publisher Copyright:
© The Royal Society of Chemistry.