J.W. Guan, P. Lu, H.M. Ding, L. Gaburici, S. Mihailov, C.T. Kingston
National Research Council Canada,
Canada
Keywords: nanomaterial, Boron nitride nanotubes (BNNTs), optical fiber, fiber optical sensing, fiber bragg grating (FBG)
Summary:
Boron nitride nanotubes (BNNTs) as an advanced emerging nanomaterial have been developed rapidly in research from their synthesis, characterization and purification in recent years. Their excellent mechanical strength and lightweight due to their one-dimensional and hollow structures with high aspect ratios, chemical resistance as well as electrically non-conductive and highly thermal stable characteristics have attracted vigorous research activities in exploration of their applications across different disciplines. One of them is the potential application of BNNTs as a multifunctional nanomaterial for sensing developments, especially in fiber optical sensing applications by taking their inherent inter-tube bundling and interfacial chemical binding through surface functional groups, where a controllable BNNT nonwoven network and coating layer can be constructed from a water-soluble solution on the fiber optical sensor devices, which provides accessible approach to detect the sensitivities of the sensor device to its environmental changes with respect of temperatures, humidity, chemicals, gases and possible radiations of any kind due to the high radiation cross sections of B atoms especially the isotope element content of B-11. It is highly demanded for confined space, high temperature, dangerous environment such as with full radiations, corrosion atmospheres and extreme weather conditions. Fiber optical sensor devices with hybrid of BNNTs can play a key role for detection and monitoring in those cases that other known sensing materials are unable to withstand and perform as expected. We will report our recent progresses on the development of BNNTs as a sensing active material with fiber optical sensor devices designed with an optical fiber taper and Fiber Bragg grating, and further we would also update the latest outcome with other aspects such as nonlinear property of BNNT micro-assembly and discuss their potential sensing applications.