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CEAS REU Project 4

Nathan Duderstadt, Chemical Engineering, University of CincinnatiStoney Sutton, Electrical Engineering, University of CincinnatiKate Yoshino, Engineering Physics, Taylor University

Dr. Vikram Kuppa and Ms. Yan Jin

Synthesis of Solar Cell Materials, and Fabrication of Novel Polymer-Based Solar Cells

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Introduction

Why solar cells?

Why ORGANIC solar cells?

What is graphene and what role does it play?

3Background Literature Review

Solar Radiatio

n

Charge Generation

Electric Current

Charge Transport

to Electrodes

In a semiconductor, the energy from the sun both moves the electron to an excited state, but also creates a hole (positive charge) in its place.

ehHighest OccupiedMolecular Orbital

Lowest UnoccupiedMolecular Orbital

Animation and concepts adapted from Dr. Vikram Kuppa’s presentation on organic photovoltaics

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Picture from: Deibel, Carsten, and Vladimir Dyakonov. (2010). " Polymer–fullerene Bulk Heterojunction Solar Cells.." Vol. 73.9, pp. 1-39.

Organic Photovoltaic Devices

The problem with semiconductors in solar cell applications is separating these particles and TRANSFERING them to their electrodes.

In order to accomplish this, we use two material, like seen to the right.

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Cell Structure

Aluminum (Cathode)

Lithium Fluoride

Active Layer (P3HT:F8BT:Graphene)

PEDOT:PSS

Indium Tin Oxide (Anode)

Glass Slide

The thickness of the cell is approximately without the glass slide is approximately 500 nm in thickness.

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Cell Structure

Aluminum (Cathode)

Indium Tin Oxide (Anode)

Active layer

Glass Slide

Solar Cell

7Project GoalDetermine how graphene makes solar cells more efficient

Learn the basics of Organic Photovoltaic (OPV) research

Gain expertise in making and characterizing OPV cells

Understand methods of fabricating graphene from graphite

Incorporate graphene in OPV cells

Differentiate between processing techniques and their influence on the solar cell

Evaluate graphene content on cell performance

Project Objectives

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Tasks1. Learn methods for making graphene solutions

and fabricating solar cell devices

2. Prepare and analyze graphene solutions for use in solar cell polymers

3. Fabricate solar cell devices and perform thermal treatment

4. Characterize the cell through various testing

5. Conduct morphology and conductivity studies on the polymer films with different graphene concentrations

6. Report writing and presentations

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Timeline

Task1 2 3 4 5 6 7 8

Training: Make Graphene Solution, Fabricate Solar

Cell                

Graphene Solutions: Prepare, Characterize,

and Blend                

Polymer Films: Make and Anneal Polymer Layers, Add to Cells                

Solar Cell Testing: Cell Efficiency for Varying

Graphene Concentrations                

Work on Deliverables: Paper, Presentation,

Poster                

Week

10Research Training Received

Lab Safety Training

Making Graphene Solutions

UV Spectrophotometer Blending P3HT and Graphene

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Atomic Force Microscope

Research Training ReceivedSpin Coating Procedure

Transmission Electron

Microscope

Performance Testing

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Progress MadeTraining is mostly

complete!

Created first set of cells (during training)

Tested first set of cells

Currently processing data

Started beginning processes of creating second batch with varying concentrations

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Questions?