Abstract
This study reports the development of functional optical limiting materials composed of pristine graphene (GQDs), nitrogen-doped (NGQDs) and sulfur-nitrogen co-doped (SNGQDs) graphene quantum dots covalently linked to mono-amino substituted zinc phthalocyanine (Pc). Open aperture Z-scan technique was employed to monitor the behaviour of the conjugates under tightly focussed Gaussian laser beam using a mode-locked Nd:YAG laser delivering 10 nanosecond (FWHM) pulses at 532 nm wavelength. Nonlinear effect due to reverse saturable absorption was the predominant mechanism; and was attributed to the moderately enhanced triplet population. The major factor(s) responsible for the enhanced nonlinearities in the Pc-NGQDs and Pc-SNGQDs was fully described and attributed to the surface defects caused by the presence of heteroatoms of N and S.
| Original language | English |
|---|---|
| Pages (from-to) | 755-766 |
| Number of pages | 12 |
| Journal | Journal of Fluorescence |
| Volume | 27 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 4 Jan 2017 |
| Externally published | Yes |
Bibliographical note
Funding Information:This work was supported by the Department of Science and Technology (DST)/Nanotechnology (NIC) and National Research Foundation (NRF) of South Africa through DST/NRF South African Research Chairs Initiative for Professor of Medicinal Chemistry and Nanotechnology (UID 62620) and Rhodes University.
Publisher Copyright:
© 2017, Springer Science+Business Media New York.