Celebramos contribución
de
David Emmanuel Vega Herrera
MSc Energy Generation
Ingeniero Químico del IT Mérida
Final Report
SUMMARY
Thin-film solar cells have the potential to considerably decrease the
cost of photovoltaic devices by reducing by a factor of up to 200 the thickness
with compare crystalline silicon solar cells. A major limitation from thin film
solar cells is the low efficiency because of its poor light absorption.
Scattering from noble metal nanoparticles excited at their surface plasmon
resonance can be used to increased light absorption from thin film solar cells.
In the present project silver films were deposited at different deposition
rates by DC sputter coating on the surface of cleaned and cut microscope glass
slides and silicon substrates. The substrates were subsequent annealed at 150oC,
200oC and 250oC for 1 and 3 hours. The aim was to
investigate how the deposition method and different parameters used to create
Ag silver nanoparticles such as deposit thickness, temperature and time of
annealing influenced the Ag nanoparticles size that can be used to increase
efficiency of thin film solar cells. The silver nanoparticles were
characterised using techniques such as Dark field microscopy used to observe
the scattered light from the nanoparticles, Scanning electron microscopy to
investigate the size, distribution and morphology of the nanoparticles and
X-ray diffraction to identify the crystalline phases of the silver
nanoparticles. The results show that by increasing the temperature and
annealing time yields increase diameter of the nanoparticle and also modify the
morphology. The observed increase in size is attributed to coalescence and
aggregates of the deposited silver on the substrate surface. The nanoparticles
had a predominant semispherical morphology. Finally, it was found that not only
by increasing temperature and time of annealing have a direct increased in
particle diameter also the deposition rate has an influence such as in the
crystallographic phase and intensity of the formed Ag nanoparticles. Systematic
methodology of manufacture silver nanoparticles is a powerful tool that can be
used to tailor the diameter from silver nanoparticles that subsequently can be
used for increased the absorption by thin film solar cells.
Supervsor: Dr Richard
Potter
School of Engineering
University of Liverpool
Brownlow
Hill, Liverpool, L69 3GH
Para citar:
Vega Herrera, D.E.
(2014) Plasmonic Silver Nanoparticles (NPs) for enhanced solar applications. Final Report, Scholl of
Engineering. University of Liverpool. 88p.
