dc.description.abstract | The search for new ways of harvesting energy from the sun led to development
of dye-sensitized solar cells (DSSC) by O Regan and Grätzel in 1991.
These solar cells are built up by a nanoporous semiconductor, a dye that is sensitized
onto the aforementioned semiconductor, and an electrolyte acting as a
redox shuttle. Calculations performed by Venkatraman et al. at NTNU, present
phenothiazine dyes as promising candidates for DSSC. A series of dyes, the
MFV2/DMA1-series, has been synthesized where the structure element known
as the π-bridge is being varied. The π-bridges influence the region where the
dye can absorb light, and the excited dye s ability to inject electrons to the conducting
band of the semiconductor.
Two novel dyes for DSSC, DMA1-3 and DMA1-4, has been synthesized. Following
a five-step synthesis, DMA1-3 was synthesized in a total yield of 31%.
The seven-step synthesis of DMA1-4 was performed in a total yield of 20%, the
π-bridge building block for this dye was synthesized in a five-step process in
yields of 1-4%. The novel dyes DMA1-3 and DMA1-4 were characterized as
dyes for DSSC, along with 5 other dyes synthesized previously in the research
group by master student Vold and the author. The dye DMA1-1 displayed the
best DSSC-performance, with a short-circuit current density of 8.88 mA cm−2
leading to a power conversion efficiency of 3.90% under solar simulation with
AM 1.5 G conditions. | en |