臺灣博碩士論文加值系統

The electron transport layer (ETL) plays a crucial role in facilitating electron extraction and inhibiting recombination in perovskite solar cells. Reduced graphene oxide (RGO) is a potential complement to the common ETL material TiO2 thanks to its excellent electrical conductivity and mobility and the suitability for scalable, low-temperature solution-processed deposition. RGO powder is synthesized through microwave-assisted hydrothermal method, and various amounts of o-phenylenediamine (OPD) are added into the precursor to create Nitrogen-doped RGO of different doping levels. The as-synthesized RGO samples characteristics are examined by XRD, XPS and Raman spectroscopy. The perovskite layer of CH3NH3PbI3 is deposited on RGO and TiO2 using a two-step spin coating process, and the as-deposited perovskite characteristics are examined through photoluminescence and UV-Vis spectroscopy. Finally, photovoltaic performance measurements of completed RGO-integrated devices is conducted under illumination of 1 Sun AM 1.5G sunlight simulator.

TABLE OF CONTENTS
ABSTRACT III
ACKNOWLEDGEMENTS IV
TABLE OF CONTENTS V
LIST OF FIGURES VIII
CHAPTER I INTRODUCTION 1
1.1 Research Background 1
1.2 Motivation and Objective 2
CHAPTER II LITERATURE REVIEW 3
2.1 Fundamentals of Perovskite Solar Cells 3
2.1.1 The development from dye-sensitized solar cells (DSC) 3
2.1.2 Organometal halide perovskites 5
2.1.3 Working mechanism of perovskite solar cells 8
2.1.4 Types of perovskite solar cells 9
2.1.5 Important parameters of solar cells 11
2.2 Graphene and its various forms 14
2.2.1 Pristine graphene 14
2.2.2 Graphene oxide (GO) 14
2.2.3 Reduced graphene oxide (RGO) 14
2.3 Graphene-based Materials in Perovskite Solar Cell Research 15
2.3.1 Graphene for semi-transparent electrodes 15
2.3.2 Graphene for electron transport layer 16
2.3.3 Graphene for hole transport layer 16
CHAPTER III RESEARCH DESIGN AND METHODOLOGY 18
3.1. Synthesis of Reduced Graphene Oxide 18
3.2. Solar Cell Fabrication 18
3.2.1 Substrate preparation 18
3.2.2 Electron transport layer deposition 19
3.2.3 Perovskite layer deposition 19
3.2.4 Hole transport layer and top electrode deposition 20
3.3. Characterization 20
3.3.1 Raman spectroscopy 20
3.3.2 X-ray diffraction (XRD) 21
3.3.3 X-ray photoelectron spectroscopy (XPS) 23
3.3.4 Photoluminescence spectroscopy (PL) 24
3.3.5 UV-Vis / NIR spectroscopy 25
3.3.6 Solar cell performance characterization 25
CHAPTER IV RESULTS ＆ DISCUSSION 27
4.1. Material Characterization of Reduced Graphene Oxide 27
4.1.1.XRD diffraction patterns 27
4.1.2 Raman characteristics 29
4.1.3 XPS chemical analysis 30
4.2 Characterization of Perovskite Layer deposited on top of RGO 34
4.2.1 Photoluminescence spectroscopy 34
4.2.2 UV-Vis spectroscopy 35
4.3 Solar cells Performance Measurements 35
CHAPTER V CONCLUSION 37
REFERENCES 38

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