Developing functional ceramic fibre materials for ultralightweight mobile sensors and energy harvesting devices

This project focuses on the design of functional ceramic fibre materials and the advanced characterisation of their electronic properties. Ceramic fibres can possess notable piezoelectric coefficients depending on the composition and manufacturing process. Such piezoelectric ceramic fibres can generate strains up to 0.63% in response to applied electric fields, making them suitable for actuator applications. Factors that affect this performance include the fibre diameter, grain sizes, fibre composition, and their manufacturing. The figure below shows an example of how precursor chemistry and production temperature can influence the morphology of hierarchically porous TiO2 fibres coupled with plasmonic Au nanoparticles.

Piezoelectric ceramic fibers can be used as fillers in composite materials to be used in smart structures, sensors, and actuators that can be of particular use in harsh environments where their thermal and chemical stability is advantageous. Alongside this, their ability to convert mechanical energy into electrical energy makes piezoelectric ceramic fibres potential candidates for energy harvesting applications. Currently, piezoelectric ceramic fibres do not match nor exceed the performance of bulk ceramic materials. Moreover, whist ceramic fibres offer enhanced flexibility they have yet to be integrated into more complex structures.

The candidate will explore whether our recent findings on the in situ creation of 3D fibre assemblies can be applied to piezoelectric ceramic precursor system and will evaluate their structure, composition, and electrical performance using state-of-the-art spectroscopic and imaging techniques. The candidate will develop synthetic methods for electrospinning 3D piezoceramic fibre assemblies and establish protocols for their structure and compositional characterisation. Advanced spectroscopic analysis of the fibres and their electrical performance will also be explored. For example, THz spectroscopy allows for non-contact and non-destructive characterisation of ceramic fibres allowing a series of complementary studies to assess the porosity of ceramics, crack defects, voids, or any inclusions that may affect their electronic response.

QinetiQ has been developing UK sovereign supply of oxide and carbide ceramic fibres over the past 12 years including continuous and short/chopped varieties. They have developed a pilot manufacture capability including research into efficient fibre spinning and winding. including bespoke manufactured fibres for purposes including piezoelectric energy harvesting.