New materials for photocatalysis and photovoltaics

Lafta, Abbas Jassim Attia (2013) New materials for photocatalysis and photovoltaics. PhD thesis, University of Glasgow.

Abstract

Photocatalytic processes are of widespread interest. Among different types of
photocatalytic material TiO2 is the generally considered amongst the best due to its
favourable physical and chemical properties. In recent decades, photovoltaic devices have
been widely studied to provide alternative routes to energy and reduce dependency upon
fossil fuel. Solar photovoltaic are cells capable of harvesting of sunlight into electrical
power. This technology is one of the most promising routes in the search for sustainable
and renewable sources of energy. The study presented in this thesis relates to the
preparation and characterization of a range of different materials which can be applied in
photocatalytic processes and for photovoltaic devices.
The photocatalysis work has been focused mainly upon modification of the various phases
of titanium dioxide. This has been undertaken via doping with nitrogen by treatment with
ammonia at different temperatures. In addition, samples containing Al, Co and Cu dopants,
as well as their N doped counterparts, have been prepared, characterized and tested. The
photocatalytic activity was screened by following photocatalytic decomposition of an
aqueous solution of methylene blue using a light source containing various components in
the UV and visible regions. For selected samples, the photocatalytic activity for
polymerization of methyl methacrylate and styrene has been determined with the aim of
producing composites.
In terms of potential photovoltaic materials, the synthesis of novel viologen compounds
and polymerization via electrochemical and chemical means has been undertaken.
Different viologen monomers have been synthesized with various moieties in conjugation
to a phenanthroline core to afford novel push-pull systems. These compounds have
incorporated both TCNE and TCNQ moieties as strong electron acceptors and hence yield
chromophore with large dipole moments. In addition, novel ruthenium complexes were
prepared featuring bipyridine and phenanthroline ligands. The optical and redox properties
of these materials have been investigated. DSSCs have been fabricated form some of these
systems and their properties have been compared to dye 719.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Photocatalysis, photovoltaics, titanium dioxide, doping nitrogen over titanium dioxide, electrochemical polymerization
• Subjects: Q Science > QD Chemistry
• Colleges/Schools: College of Science and Engineering > School of Chemistry
• Supervisor's Name: Hargreaves, Dr. Justin and Cooke, Prof. Graeme
• Date of Award: 2013
• Embargo Date: 12 March 2016
• Depositing User: Mr Abbas Lafta
• Unique ID: glathesis:2013-4105
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 21 Mar 2013 12:47
• Last Modified: 15 Apr 2016 15:38
• URI: https://theses.gla.ac.uk/id/eprint/4105