报 告 人：Hark Hoe Tan 教授
Prof. Tan has been the past recipient of the Australian Research Council Postdoctoral, QEII and Future Fellowships. He has published/co-published over 400 journal papers and 6 book chapters with a total of over 12000 citations and a h-index of 54. He is also a co-inventor in 4 US patents related to laser diodes and infrared photodetectors. His research interests include epitaxial growth of low-dimensional compound semiconductors, nanostructured optoelectronic devices and ion-implantation processing of compound semiconductors for optoelectronic device applications. Prof. Tan is a Senior Member of the IEEE and was the Distinguished Lecturer for IEEE Nanotechnology Council (2016 & 2017) and IEEE Photonics Society (2016-2017).
Nanowires are anisotropic structures which have diameters of several to tens of nm’s while their lengths could be µm’s long. Thus they have a very high aspect ratio, large surface-area-to-volume ratio and allow carrier/photon confinement in two dimensions, which lead to their unique properties. Inverse opals are highly ordered macroporous materials consisting of a face-centered cubic crystal, formed through the infiltration of another material into a sacrificial opal template, and followed by the removal of the spheres. They are ideal for photocatalysis due to their inherent structural properties such as a large surface area, tunable macroporosity, and stability. The interconnected macroporous architecture allows accessibility of the electrolyte to the active sites of the photocatalyst, and also provide long-range ordered paths for electron transport throughout the electrode, thus improving charge migration. In this talk, I will present the III-V semiconductor nanowire activities at The Australian National University. Various issues related to nanowire growth such as crystal structure, tapering, crystalline defects and formation of axial and radial heterostructures will be discussed. Results from three types of device-nanowire lasers, solar cells and photoelectrodes for solar water splitting will then be presented.