Scheme: University Research Fellowship
Organisation: University of Cambridge
Dates: Oct 2007-Sep 2012
Summary: I look at nanostructured systems using electron microscopes, and in particular I study photoactive nanomaterials like titanium oxide and zinc oxide to understand how they interact with light at the nanoscale. In the past few years there has been a great emphasis on the need for renewable energy sources. A great effort is now going into the development of cheap and robust photoelectrochemical devices based on nanostructured materials to harvest solar power, but so far the overall power conversion efficiency is max 10-12%. If we want to improve these very promising solar cells, then we must learn how they behave on the nanoscale, under realistic working conditions.
In the past year we have used the transmission electron microscope (TEM) as a tool to understand solar cell behaviour in three dimensions, which improves the current understanding of electron transport through the nanostructured photoanode. Using our 3D datasets we have been able to determine the values of surface area, polymer penetration, connectivity, tortuosity, which can be correlated with macroscopic measurements performed on the same devices.
Another interesting discovery we have made this year involves a new titania-based photocatalytic material which can degrade aromatic compounds and bacteria using visible light, rather than UV light like standard titania. This material, activated by radiation such as that of office lamps, is able to decompose dyes and purify water very fast, and could be used to treat waste waters as well as flood waters. We have also measured hydrogen production levels considerably higher than for other photocatalytic systems. In the past few weeks we have been preparing a patent application to protect this invention.
Scheme: Dorothy Hodgkin Fellowship
Dates: Oct 2004-Sep 2007
Summary: This project summary is not available for publication.