Inorganic Semiconductor Nanocrystal Synthesis Metal Oxide Gas Sensors Quantum Dots Inorganic Semiconductor Nanostructures Carbon Nanotubes Spectroscopy

Research Interests – Quantum Dots, Semiconductor Nanocrystals, Plasmonic Nanostructures I lead a research team investigating the shape-and-size controlled synthesis of inorganic semiconductor nanocrystals and quantum dots, principally by hydrothermal and microwave-based methods. The potential applications for these monodispere nanocrystals in the sphere of photonics and photocatalysis are truly enormous. Our interests focus on harnessing plasmonic metal nanoparticles and semiconductor nanocrystals for photocatalysis and nonlinear optics. Nanoparticle-Based Plasmonics & Nonlinear Optics Research: Our group is exploring the potential of an exciting new means to convert visible light into UV light using extremely compact, precisely coupled-nanoparticle systems. The novelty of this approach is that we intend to use localised surface plasmons supported by the NPs to stimulate nonlinear interactions in a coupled NP-QD system. Our thesis is that when noble metal nanoparticles (NPs) are coupled to semiconductor quantum dots (QDs), together they can effectively absorb visible light and generate UV light. Collaboration with Assoc. Prof. Esa Jaatinen & Dr Kristy Vernon, QUT Physics. ZnO Nanowire Gas Sensors: for agricultural & mining applications. Nanowire sensors demonstrate superior performance and low power consumption. They employ the same metal oxide materials used in dye-sensitised solar cells and integrate these devices together yielding miniature, self-powered, greenhouse-gas sensors for application in networks for remote monitoring. Titania Nanotubes: Titanium dioxide is a promising photocatalyst which can break-down organic pollutants. We have investigated hydrothermal methods to synthesise nanotubes of titania. The structural changes that occur following hydrothermal treatment have been followed using transmission electron microscopy (TEM). Changes in Phase, structure and binding have been followed using powder x-ray diffraction, electron diffraction and Fourier Transform Raman spectroscopy.

Shortell MP, Jaatinen EA, Chang J, Waclawik ER, (2014) Using pulse transit delay in Z-scan to discriminate between excited-state absorption and other nonlinear processes in ZnO nanocones, Optics Express p6222-6228 Shortell MP, Fernando J, Jaatinen EA, Waclawik ER, (2014) Accurate measurement of the molecular thickness of thin organic shells on small inorganic cores using dynamic light scattering, Langmuir p470-476 Chang J, Waclawik ER, (2013) Controlled synthesis of CuInS2, Cu2SnS3 and Cu2ZnSnS4 nano-structures: insight into the universal phase-selectivity mechanism, CrystEngComm p5612-5619 Chang J, Rasin A, Wang H, Liu H, Li R, Wang P, Waclawik ER, (2013) ZnO nanocones with high-index {101_1} facets for enhanced energy conversion efficiency of dye-sensitized solar cells, The Journal of Physical Chemistry Part C: Nanomaterials, Interfaces and Hard Matter p13836-13844 Chang J, Waclawik ER, (2012) Facet-controlled self-assembly of ZnO nanocrystals by non-hydrolytic aminolysis and their photodegradation activities, CrystEngComm p4041-4048 Morgan D, Liu H, Frost RL, Waclawik ER, (2010) Implications of precursor chemistry on the alkaline hydrothermal synthesis of titania/titanate nanostructures, The Journal of Physical Chemistry Part C: Nanomaterials and Interfaces p101-110 Giulianini M, Waclawik ER, Bell J, Scarselli M, Castrucci P, De Crescenzi M, Motta N, (2009) Poly(3-hexyl-thiophene) coil-wrapped single wall carbon nanotube investigated by scanning tunneling spectroscopy, Applied Physics Letters p1-3 Morgan D, Zhu HY, Frost RL, Waclawik ER, (2008) Determination of a morphological phase diagram of titania/titanate nanostructures from alkaline hydrothermal treatment of degussa P25, Chemistry of Materials p3800-3802 Musumeci AW, Silva GG, Liu J, Martens WN, Waclawik ER, (2007) Structure And Conductivity of Multi-Walled Carbon Nanotube/Poly(3-Hexylthiophene) Composite Films, Polymer p1667-1678 Jasieniak J, Johnston MR, Waclawik ER, (2004) Characterization of a Porphyrin-Containing Dye-Sensitized Solar Cell, The Journal of Physical Chemistry Part B: Condensed Matter, Materials, Surfaces, Interfaces & Biophysical p12962-12971