Understanding materials at the nanoscale for improved thermoelectric performance

The aim of this iCASE is to create a fundamental understanding of thermoelectric (TE) performance of a benchmark TE material system (e.g. Bi₂Te₃) in various nanostructures characterizing the materials to gain insights on fundamental nanostructure-conductivity mechanisms. From this benchmarking, dedicated nano-systems of earth-abundant materials will be investigated to transfer the fundamental understanding in an effort to design novel materials systems with greater figure-of merit values (ZT) than the current best-in-class (Bi₂Te₃).

The limited efficiency of thermoelectric generators (TEGs) has restricted their use despite the large amounts of waste heat generated from primary energy sources. Currently, commercial TEGs use Bi₂Te₃ having a figure of merit (ZT) performance of 1 at around room temperature but the scarcity of tellurium and the rigid device design further limits wide-scale adoption of the technology.

A fundamental challenge in realizing high-performance bulk TE materials is due to the fact that both the electrical and thermal conductivity are related via charge carrier concentration such that optimizing one parameter negatively impacts on the other. Through nano-structuring a large number of interfaces can be realized, increasing phono scattering and reducing thermal conductivity, and much research has been devoted to exploration of new TE nanomaterials to exploit this.

Linking material properties at the nanoscale with TE performance is a corner-stone of progressing the design of next-generation TE materials. This has been explored in Si nanowire systems, but many effects contribute to ZT through various mechanisms such as band structure, interface scattering and localised lattice effects. With the emergence of new complex morphology nano-systems (e.g. carbon nanotubes) understanding structure-property relationships more is vital to ascribing microscopic effects to realising optimized materials with increased ZT values

Candidates must hold a first-class degree or equivalent or distinction at masters level.

This studentship is only available to UK students. 

English language requirements

IELTS requirements: for non-UK-based courses an English requirement of 6.5 or above (or equivalent) with 6.0 in each individual category.

• Advanced Technology Institute (ATI)
• Nanoelectronics Centre (NEC)