| dc.description.abstract | The objective of this project was to investigate the effect of the morphology of titanium
dioxide (TiO2) nanoparticles on the electron transport properties and light harvesting potential in
a dye sensitized solar cell (DSSC). Particular attention was given to develop synthetic methods
to produce metal oxide photocatalysts with similar crystallite size, with different morphologies
(spheres, fibers, hierarchical spheres, and globular structures) with the aim of studying the
relationship between morphology and photocatalytic activity. The addition of CNTs to the
synthesis showed that they acted as nucleation sites and altered the morphology. Materials were
fully characterized using Raman, SEM, XRD, BET, and FTIR.
The photocatalytic activity of the as-synthesized materials was tested in a DSSC
configuration and characterized using electrochemical impedance spectroscopy. It was found that
the different morphologies had different light scattering properties which influenced the
efficiencies. Based on these preliminary results, the nanofibres prepared in heptane performed
the best, with good dye loading, electron lifetime and diffusion coefficient. The addition of a
scattering layer using hierarchical spheres showed promising results in decreased transparency
and increased efficiency. The addition of CNTs had an adverse effect, this could be due to light
blocking by the black CNTs and increased recombination with the electrolyte. | en |
