Martin Allen and collaborators (University of Canterbury) affiliated with the MacDiarmid Institute for Advanced Materials and Nanotechnology
Tin oxide is a semiconductor which can be synthesised into nanostructures that are circular or cylindrical. Tin oxide possesses a crystalline structure which should create square profile nanotubes. Square nanotubes show promise for use in batteries, catalysis and even molecular machines or nanoscale syringes for targeted drug delivery.
Efforts to synthesise ordered arrays of square tin oxide nanotubes have so far resulted in structures that are either poorly aligned, structurally irregular in nature, or exhibit rough sidewalls.
The research team developed a scalable method for producing square tin oxide nanotube arrays with smooth sidewalls. With the unique structure identified, the researchers used the Soft X-ray Spectroscopy (SXR) beamline to reveal further details of the chemical and electronic properties of the nanotubes. These ordered arrays of square tin oxide nanotubes are expected to prove useful for gas/chemical sensing and catalytic applications, even in situations where elevated temperatures are encountered.
To demonstrate their potential in real world sensing applications, prototype Schottky diodes, field effect transistors and gas sensing devices were fabricated using individual nanotubes. In each instance, the nanotubes exhibited robust electrical and sensing performance.
Reference:
Scott JI, Adams RL, Martinez-Gazoni RF, Carroll LR, Downard AJ, Veal TD, Reeves RJ, Allen MW. 2023. Looking outside the square: The growth, structure, and resilient two-dimensional surface electron gas of square SnO2 nanotubes. Nano Micro Small 19(28):2300520. https://doi.org/10.1002/smll.202300520
