Charge carrier dynamics in colloidal nanocatalysis

High energy combustible chemicals derived from photocatalytic reactions, i.e. solar fuels, are of current research interest as they are likely to play a major role in a future green and sustainable energy mix. Photocatalytic systems based on colloidal nanocrystals are particularly attractive as a low-cost, potentially high-efficient solution to solar hydrogen generation.

A major bottleneck in the use of colloidal semiconductor nanocrystals is the efficient use of photogenerated holes as they frequently undergo relaxation pathways that destroy either the nanocrystal itself or the stabilising ligand shell through oxidation. Preliminary work in our group showed that the temporary dynamics and potentially the reaction pathways of the photohole can be manipulated by the anchoring group of the ligand shell.

This project will systematically investigate how to manipulate photohole dynamics in colloidal nanocrystals using different co-catalysts and ligand anchoring groups with the aim to develop photocatalytic nanosystems optimised with respect to stabililty and efficiency. The project will make extensive use of a new ultrafast transient absorption spectroscopy system to gain insight into different loss and relaxation pathways on the fs to ns timescales. In addition, the project will involve basic chemical synthesis.