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Natural Dyes Co-Sensitization in Solar Cells Application:

Uv-Vis Spectra and Electrical Performance

Adriano Pamain

PhD Student

Assistant Lecturer –UDOM, Tanzania

MSc (Material Science & Engineering-NM-AIST)

BSc (Physics-USDSM)

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Fossil fuel and

Natural GasPollutions

Depleting

Solar Energy

1st Generation

2nd Generation

3rd Generation

4thGeneration???

PV Wafer based

Crystalline silicon

Thin film:

a-Si, CdTe, CIGS

Thin film:

DSCCs

Still years off: quantum dots ,

nanowires

Senthetic/M

etal

Complexes

Natural dyes

Background

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Physics behind and Principle of DSSC

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Need for increasing the absorption of entire visible spectrum.

The DSSCs made from single dyes suffer from low efficiency

due to the fact that individually they absorb very small portion

of the visible spectrum (Karki et al., 2013).

Therefore, the need for co-sensitization of dyes for broadband

absorption in the visible spectrum to improve efficiency of

DSSCs is required.

Problem Statement

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i. Fabricate a dye-sensitized solar cell based on each of

the dyes, explore their photovoltaic properties and

determine efficiency of each dye sensitized solar cells

ii. Determine the effects of co-sensitization of the

mixture of dyes on the efficiency of dye sensitized

solar cell

Objectives

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It is economically feasible harnessing Solar energy

by DSSC

Environmental friendly and hence no pollution

Can provide usable energy to inaccessible and

economically challenge community- remote areas

Cheap and affordable easily extracted from

fruits, vegetable and flowers with simple and

direct chemical procedures

Contribution to research progress

Why DSSC????????

Black grapes, Raspberry, Javaplum, Red cabbage, Hibiscus flower, and Begonia rex7

Characterization and Measurements

DSSC Solar Assembly

Counter Electrode coating

TiO2 Film deposition

TiO2 Suspension Preparation

Preparation of Each Natural dyes extract

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Extracting Anthocyanin by Ethanol

Determine and Stabilizing the

pH

Mix dye by at a ratio of 1:1 by

Volume

Methodology

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The absorption spectra of dye solutions and dyes adsorbed

on TiO2 surface will be recorded using a UV–VIS

spectrophotometer

UV-Vis Spectrum

400 500 600 700 800

0.0

0.5

1.0

1.5

2.0

2.5

3.0A

bso

rban

ce (

a.u

.)

Wavelength (nm)

Hibiscus

Begonia rex

Mixture

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J-V Curve and P-V Curve for a DSSC

OCSC

MPMP

T

MAX

VJ

VJ

P

PF

.

.

1. Power output,

2. Fill factor,

3. Solar Efficiency, in

OCSC

P

FFVJ

Pin

P ..max

Where:

JMP is the maximum current density;

VMP is the Maximum voltage

Voc is the open-circuit voltage;

Jsc is the short-circuit current density;

FF is the fill factor and;

η is the efficiency.

MPMP VJP

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Btn 0.5 to 0.82 are satisfactory range

Power output, Fill Factor (FF) & Efficiency

Thanks for listen

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