1. Carbon Nanotube-Polymethine Dye Complexes with Strong Photoluminescence William Abbot

2. Nuffield Foundation “Improve social well-being through education, research and innovation” Nuffield Research Placements – funding to experience a research project environment www.nuffieldfoundation.org/nuffield-research- placements

3. Carbon Nanotubes Essentially a rolled-up graphene sheet Single-wall and multi-wall varieties Different properties based on how they are rolled up: metallic or semiconducting http://www.physik.uni-regensburg.de/aktuell/KollSS05/Thomsen-Vortrag.htm

4. Uses of Carbon Nanotubes Materials, composites Electronics Novel methods of drug delivery

5. Aim of the Project Carbon nanotubes have a huge range of uses Problem with potential toxicity A fast, reliable but portable sensor will be required

6. Photoluminescence (Fluorescence) in Single-Wall Nanotubes Left: From Photoluminescence on Carbon Nanotubes Right: www.photon.t.u-tokyo.ac.jp Energy band gap of SWNTs depends on nanotube diameter: the larger the diameter, the smaller the band gap

7. The Photoluminescence Spectrum www.originlab.com

8. n = 1, 2, 3, 4, 5 Polymethine Dyes Absorption depends on the length of the chain (the size of n )

9. Weighing the material Graphite flake SDBS - surfactant Ultrasonication, 20 kHz, 1.25 hours Centrifugation, 30kRPM, 2 hours Mixing with DOB-719 (dye) H2OH2O Carbon nanotube powder Method Spectroscopic analysis

10. Results Several new peaks at an excitation wavelength of ~735nm appear for CNT+DOB-719

11. Carbon Nanotube-Dye Interaction

12. More efficient, so increases intensity of emitted light Carbon Nanotube-Dye Interaction

13. Conclusion Carbon nanotubes: very promising but potentially harmful Fluorescence enhancing probes for carbon nanotubes are being developed Will soon lead to sensor systems

14. Thanks for Listening www.nuffieldfoundation.org/nuffield -research-placements