Polymer-carbon nanotube composite coatings have properties that are desirable for a wide range of applications. However, fabrication of these coatings onto submillimeter structures with the efficient use of nanotubes has been challenging. Polydimethylsiloxane (PDMS)-carbon nanotube composite coatings are of particular interest for optical ultrasound transmission, which shows promise for biomedical imaging and therapeutic applications. In this study, methods for fabricating composite coatings comprising PDMS and multiwalled carbon nanotubes (MWCNTs) with submicrometer thickness are developed and used to coat the distal ends of optical fibers. These methods include creating a MWCNT organogel using two solvents, dip coating of this organogel, and subsequent overcoating with PDMS. These coated fibers are used as all-optical ultrasound transmitters that achieve high ultrasound pressures (up to 21.5 MPa peak-to-peak) and broad frequency bandwidths (up to 39.8 MHz). Their clinical potential is demonstrated with all-optical pulse-echo ultrasound imaging of an aorta. The fabrication methods in this paper allow for the creation of thin, uniform carbon nanotube composites on miniature or temperature-sensitive surfaces, to enable a wide range of advanced sensing capabilities.

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In situ mass spectrometry measurements has been used to study as phase intermediates in CVD of TiO2 thin films.

The synthesis of thermochromic monoclinic vanadium(IV) oxide (VO 2 (M)) thin films and vanadium oxide nanocrystals from a molecular precursor, [{VOCl 2 (CH 2 (COOEt) 2 )} 4 ] is described. Thin films were synthesised using aerosol assisted chemical vapour deposition (AACVD) onto glass substrates at high temperatures and were subsequently characterised and tested for thermochromic efficiency. The film's suitability as smart, energy efficient window coatings was investigated by calculating their solar modulation potential. Thin films were also doped with tungsten to lower their metal to semiconductor transition temperature (MST) through the addition of tungsten(VI) phenoxide during the AACVD process, lowering the MST from a typical B70 1C for an undoped VO 2 (M) thin film to B50 1C for a typical W-doped example. The optimum deposition temperature of 550 1C produced films with thermochromic properties (solar modulation of 15.9%) comparable to the highest values reported. In addition, vanadium oxide nanostructures were synthesised using the thermal decomposition of [{VOCl 2 (CH 2 (COOEt) 2 )} 4 ] and their shape controllably tailored by varying surfactant concentration and type. Thin films and nanostructures were characterised using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDS). Thermochromic measurements were measured using UV-Vis spectroscopy with a variable temperature stage.