Principal Investigator: Dr Nick Bennett
Co-Investigator: Prof Roger Webb (Surrey)
Research Associate: Dr Peter Szabo
Funding: EPSRC

Over 15 TW of power is continually lost worldwide in the form of waste heat. Thermoelectric generators (TEGs) offer one method of reducing this waste, by harvesting the heat and using it to create electrical power. While the conversion efficiency of TEG devices is often <10%, the sheer abundance of waste heat, offering a free fuel source, makes TEGs appealing for many diverse applications.

This proposal is aimed at thin-film TEGs (active thickness, 1-20 micrometres), forecast to be a core market sector in the future, with the advent of flexible/wearable electronics, and with the increased uptake of sensors, all of which require low-power. If TEGs can be produced at low-cost and with increased functionality (e.g. flexible), their potential is significant to act as a power source for future electronic devices that improve our quality of life.

As an alternative to generators, the same thin-film technology can also be used in reverse for small-scale heating/cooling applications, with thin-film modules already used for chip-cooling in high-performance electronics (space, military and aerospace applications). Silicon-based technologies underpin the global electronics industry due to their many practical advantages. These same benefits would extend to TEGs were it not for the poor thermoelectric conversion performance of silicon.

This project will undertake pioneering materials work in the area of “vacancy-rich silicon” – essentially silicon with many atoms removed at the atomic level – building on initial work carried-out by us, which has shown vacancy-rich silicon to be competitive with other state-of-the-art thermoelectric materials. The realisation of flexible thin-film TEGs based on vacancy-rich silicon will represent a transformative step applicable to numerous applications, including power generation and heating/cooling within clothing, as targeted specifically by us in co-operation with our industry partners.