Pulsed laser synthesis of functional nanomaterials
Focused, pulsed laser light with short wavelengths is absorbed in a thin surface region for the majority of materials, allowing melting and vaporisation at the focal point. This forms the basis of a very versatile material deposition and modification system. This research concentrates on new techniques for using these high power, short pulsed, lasers for the production of technologically relevant nanomaterials, such as nanofoams, nanocoils and nanotubes.
Aims and objectives
This project aims to investigate techniques using high-power, short-pulsed lasers for the production of important nanomaterials, including nanoclusters, nanotubes and nanorods of carbon and zinc oxide, with controllable electrical and optical properties. We will be addressing a full range of challenges, from obtaining a fundamental understanding of the growth processes to producing physical, chemical and biological sensors based on the products.
- Prof. Michael Ashfold (School of Chemistry, University of Bristol).
- S. J. Henley, J. Fryar, K. D. G. I. Jayawardena, S. R. P. Silva, “Laser-assisted hydrothermal growth of size-controlled ZnO nanorods”, Nanotechnology, 21, 365502 (2010).
- K.D.G.I. Jayawardena, Y.Y. Tan, J. Fryar, H. Shiozawa, S.R.P. Silva, S.J. Henley, G.M. Fuge, B.S. Truscott and M.N.R. Ashfold, “Highly conductive nano-clustered carbon:nickel films grown by pulsed laser deposition” Carbon (in press) (2011).
- K. D. G. I. Jayawardena, C. Opoku, J. Fryar, S. R. P. Silva, S. J. Henley, “Excimer laser accelerated hydrothermal synthesis of ZnO nanocrystals & their electrical properties” Appl. Surf. Sci., 257, 5274, (2010).
- K. D. G. I. Jayawardena, J. Fryar, S. R. P. Silva and S. J. Henley, “Morphology Control of Zinc Oxide Nanocrystals via Hybrid Laser/Hydrothermal Synthesis", J. Phys. Chem. C,. 114, 12931 (2010).
We have fabricated mixed carbon/nickel highly conductive nano-clustered coatings by laser ablation and used these as environmental sensors and as electrodes for X-ray detectors. We have shown that laser irradiation in solution is a rapid method of producing size and morphology controlled ZnO nanocrystals and have investigated their gas sensing properties.
We have performed extensive plume characterisation measurements using the ultra-fast imaging and spectroscopy facilities established as part of this grant and have proposed new mechanisms controlling the mixing of elements during clustering after laser ablation in background gases.