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The technique for producing quantum-sized zinc oxide (ZnO) particles is much safer than a technique that used hydrogen sulfide gas to produce cadmium sulfide and zinc sulfide nanoparticles. A further advantage of this method is the ability to sample the solution over time and hence determine the growth kinetics.

An experiment is developed for a laboratory course on nanostructures, as part of the undergraduate Bachelor of Science degree in nanotechnology at Flinders University. Designed to demonstrate the relationship between molecular order and the optical dielectric properties of the liquid crystalline state, the experiment is shown to be a useful tool for students studying nanotechnology.

Scanning probe microscopy techniques were used to study immobilized enzyme molecules of glucose oxidase (GOD) on a biosensor surface. The study was carried out in order to optimize atomic force microscopy (AFM) imaging and reveal themolecular resolution of individual GOD molecules. Chemically modified AFM tips and the light tapping mode were found to be the optimal conditions for imaging soft biomolecules such as GOD. The information obtained from the AFM images included spatial distribution and organization of the enzyme molecules on the surface, surface coverage and shape, size and orientation of individual molecules. Two typical shapes of GOD molecules were found, spherical and butterfly, which are in accordance with the shapes obtained from scanning tunnelling microscopy (STM) images. Using a model of the orientation of the GOD molecules on the surface, these shapes are assigned to the enzyme standing and lying on the surface. After AFM tip deconvolution, the size of the spherical shaped GOD molecules was found to be 12 ±2.1 nm in diameter, whereas the butterfly shapes were 16.5 ± 3.3 nm x10.2 ± 2.5 nm. Corresponding STM images showed smaller lateral dimensions of 10 _1nm_ 6 ±1nm and 6.5 ± 1 nm x5 ± 1 nm. The disagreement between these two techniques is attributed to the deformation of the GOD molecules caused by the tapping process.

The difference between solution and surface properties such as pK(sub a) is illustrated enabling students to understand the differences between nanoscale and macroscopic systems. Details regarding the usage of electrochemical instrumentation, such as a potentiostat, and of the technique such as cyclic voltammetry are given.

In this work a simple and up-scalable technique for creating arrays of high purity carbon nanotubes via plasma enhanced chemical vapor deposition is demonstrated. Inductively coupled plasma enhanced chemical vapor deposition was used with methane and argon mixtures to grow arrays in a repeatable and controllable way. Changing the growth conditions such as temperature and growth time led to a transition between single and multi-walled carbon nanotubes and was investigated. This transition from single to multi-walled carbon nanotubes is attributed to a decrease in catalytic activity with time due to amorphous carbon deposition combined with a higher susceptibility of single-walled nanotubes to plasma etching. Patterning of these arrays was achieved by physical masking during the iron catalyst deposition process. The low growth pressure of 100 mTorr and lack of reducing gas such as ammonia or hydrogen or alumina supporting layer further show this to be a simple yet versatile procedure. These arrays were then characterized using scanning electron microscopy, Raman spectroscopy and x-ray photoelectron spectroscopy. It was also observed that at high temperature (550 °C) single-walled nanotube growth was preferential while lower temperatures (450 °C) produced mainly multi-walled arrays. [ABSTRACT FROM AUTHOR]

Ruthenium porphyrin functionalized single-walled carbon nanotube arrays are prepared by using coordination of the axial position of the metal ion onto 4-aminopyridine preassembled single-walled carbon nanotubes directly anchored to a silicon (100) surface (SWCNTs-Si). The results have suggested the ruthenium porphyrin modified electrodes are excellent candidates for molecular memory devices and light harvesting antennae.

A strategy is used to investigate that the electron transfer properties of redox enzymes with microperoxidase (MP) is attached to the end of aligned single walled carbon nanotubes. In studies of the electrochemical properties of biologically relevant molecules such as hydrogen peroxide, NADH, and dopamine, carbon nano-tube-modified electrodes have shown superior performance as compared to other carbon electrodes.