The electronic structure of ZnO core-C60 shell (ZnO@C60) quantum dots (QDs) was investigated with the help of model interface analysis between ZnO QDs and C60 using in situ ultraviolet and X-ray photoelectron spectroscopy measurements. To form the ZnO QDs/C60 interface in situ, a vacuum-integrated electrospray deposition technique was employed to simulate the electronic interactions between ZnO QDs and C60 upon the formation of a ZnO@C60 core-shell structure. Photoelectron spectra of ZnO QDs/C60 interface formation were compared with those of ZnO@C60 QD and pristine ZnO QD films. The results revealed that ZnO QDs and C60 interacted via electron transfer leading to the change in ionization energy of the surface C60. This induced a negligible energy barrier between the lowest unoccupied molecular orbital level of C60 and the conduction band minimum of ZnO, which led to efficient electron transport through the ZnO@C60 QDs. (Chemical Equation Presented).
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (Grants NRF-2015R1C1A1A01055026 and 2017R1A2B4002442), Samsung Display Company, and an Industry-Academy joint research program between Samsung Electronics and Yonsei University.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films