Speaker
Description
Graphene quantum dots (GQD) are nanoparticles consisting of a single or several layers of graphene sheets whose thickness does not exceed 100 nanometers. For their ease of preparation, biocompatibility and tunable absorption and emission properties, they have become extremely popular in optoelectronics, as nanocarriers for cancer therapy drugs and in bioimaging techniques.[1]
In this work, we focus on coronene, the smallest unit of a graphene nanoflake and a zero-dimensional quantum dot. Several studies have found that coronene shows fluorescence and phosphorescence in the visible range of the light spectrum.[2] As a starting point, we unravel the excited state deactivation pathways of a single unit of coronene using the ML-MCTDH method [3] and a vibronic coupling model for the nuclear Hamiltonian, including both singlet and triplet states.
Future work will look at expanding the system size, adding further layers and pondering the effect of functionalization to explain the strong emission found by our experimental collaborators in doped carbon nanoparticles. [4]
References
[1]M. Li, T. Chen, J. Gooding, J. Liu, ACS Sens., 4, 1732-1748 (2019)
[2]S. Hirayama, H. Sakai, Y. Araki, M. Tanaka, M. Imakawa, T. Wada, T. Takenobu, T. Hasobe, Chem. Eur. J., n/a-n/a (2014)
[3]H. Wang, M. Thoss, The Journal of Chemical Physics, 119, 1289-1299 (2003)
[4]D. López-Díaz, A. Solana, J. García-Fierro, M. Merchán, M. Velázquez, Journal of Luminescence, 219, 116954 (2020)
