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THE FINAL REPORT OF THE WORK DONE ON THE PROJECT
UGC MRP(S)-0638/13-1-4KLCA039/UGC-SWRO dated 28th –Mar-2014
1. TITLE OF THE PROJECT : Preparation and Characterisation of Semiconductor
Nanomaterials for the Fabrication of Solar Cells
2. NAME AND ADDRESS OF THE PRINCIPAL INVESTIGATOR : Dr. BINI S,
Asst. Professor,
Dept. of Physics,
SKVC, Thrissur,
Kerala
PIN- 680011
3. NAME AND ADDRESS OF THE INSTITUTION :
Sree Kerala Varma College,
Kanattukara P O,
Thrissur,
Kerala
PIN- 680011
4. UGC APPROVAL LETTER NO. AND DATE :
MRP(S)-0638/13-1-4KLCA039/UGC-SWRO
dated 28th –Mar-2014
5. DATE OF IMPLEMENTATION … 18/06/2014
6. TENURE OF THE PROJECT …… 18/06/2014 to 30/06/2014
7. TOTAL GRANT ALLOCATED …… Rs.2,00,000/…………………………………
8. TOTAL GRANT RECEIVED ………Rs.1,45,000/9. FINAL EXPENDITURE ……………Rs.1,45,000/10.TITLE OF THE PROJECT :
Preparation and Characterisation of Semiconductor Nanomaterials for the
Fabrication of Solar Cells
11. OBJECTIVES OF THE PROJECT :
The main objective of the project was the preparation of semiconductor nano
materials using low cost techniques, which can be used for the fabrication of solar cells.
12. WHETHER OBJECTIVES WERE ACHIEVED : Yes
13. ACHIEVEMENTS FROM THE PROJECT :
In the present work four prominent photovoltaic materials in the nano form
were prepared and attempts were made to fabricate solar cells using these materials.
The structural and optical properties of these materials and their variation with
various synthesis parameters were studied.
14. SUMMARY OF THE FINDINGS :
During this project, four prominent photovoltaic materials viz, CdS,Cu xS,TiO2
and ZnS were prepared using the simple and low cost Chemical Bath Deposition
(CBD) method. Also attempts were made to prepare solar cell structures using the
prepared materials. A brief description of the workdone on each material and the
results obtained are given below.
i)
Cadmium sulphide : CdS in the nano form were prepared using Cadmium
chloride and thiourea. Tri Ethanol Amine (TEA) was used as the
complexing agent. The nano material was characterized using assorption
spectroscopy, XRD and FTIR. The particle size was estimated to be
6.991nm. The prepared nanomaterial was used to fabricate Dye sensitized
solar cell. I-V Characteristics were drawn and efficiency was calculated.
The optical band gap of the CdS nano-films have been calculated from
absorbance vs energy graph using UV-VIS-NIR spectra . The shift of
absorption from the reported bulk value for CdS indicated quantum
confinement effect. Effect of various experimental conditions like amount of
complexing agent and temperature were studied. which shows that the
particle size decreases as the amount of TEA increases and also size
increases as the reaction temperature increases.
ii)
Copper Sulphide : In this present work we have made an attempt to
prepare Cu2S nanofilms using nano CdS by clevite process. This work also
includes the fabrication of CdS-Cu2S solar cell. The samples were
characterized by absorption spectroscopy, XRD and FTIR spectroscopy.
The optical band gap of the Cu2S nano-films have been calculated from
absorbance vs energy graph using UV-VIS-NIR spectra. Effect of various
experimental conditions like thickness variation and time period of
immersion in CuCl2 solution were studied.
XRD spectrum showed hexagonal crystal structure for both CdS and
Cu2S. The particle size of both the samples were calculated using Debye
scherrer’s formula. Fourier transform infrared spectroscopy used to
measure the vibrational frequencies of bonds in the molecule. Using Hot
probe measurement showed that the prepared CdSnano material is n-type
and Cu2S flim is p-type in nature.
iii)
iv)
Titanium dioxide : nano crystalline TiO2 was prepared by sol gel
precipitation route using titanium tetra isopropoxide. The XRD pattern of
prepared nano-TiO2 and standard powder were recorded. Nano TiO2
powder with grain size of ~ 6 nm could be obtained. In the FTIR spectra,
the peaks observed around 460-560 cm-1 were due to stretching and
bending vibrations of -OH groups. Energy gap of nano TiO2 was found to
be 3.83eV.
Zinc Sulphide: prepared nano ZnS films using low cost Chemical Bath
DepositionTechnique. From the analysis of absorption spectra we can
conclude that the bandgap energy of ZnS nanomaterial decreases with
increase of time of deposition. In comparison with ZnS thin flim, nano ZnS
material has high absorbance. X-ray diffraction pattern indicates the very
good hexagonal wurtzite structure of ZnS nano crystals. The three
prominent peaks of samples corresponding to lattice planes
(1014),(012),(2010) match very well with the hexagonal wurtzite ZnS
structure. (JCPDS pattern 01-089-2144).Hot probe measurement showed
that both the prepared ZnS nano material and ZnS thin flim are n-type in
nature.
15. CONTRIBUTION TO THE SOCIETY :
Energy holds the key to all round progress and prosperity of any country.
Increase in population and changes in lifestyle results in excessive consumption of
energy. Due to the excessive energy consumption, the conventional fossil fuels are
being depleted away rapidly. In this context, solar cells have received great
attention as an alternate energy source. The high cost of photovoltaic systems is a
key factor affecting its large scale usage. To reduce the cost, semiconductor
materials with good photovoltaic properties should be developed using simple and
cost effective techniques. This project is a humble attempt in this direction. During
this project, a number of semiconducting nanomaterials like CdS, CuxS, ZnS, TiO2
with good photovoltaic properties were prepared using low cost Chemical
Deposition Technique and were characterized. In addition, a green chemistry
approach
was
incorporated
to
minimize
the
wastage
of
chemicals.
16. WHETHER ANY Ph.D. ENROLLED/PRODUCED OUT OF THE PROJECT
: No
17. NO. OF PUBLICATIONS OUT OF THE PROJECT : 1
(1under communication)