Plasmonic Organic Solar Cells (eBook)

Dr. Tze-Chien Sum is an Assistant Professor at the School of Physical and Mathematical Sciences (SPMS), Nanyang Technological University (NTU), where he leads the Femtosecond Dynamics Laboratory. He received his Ph.D. in 2005 from the National University of Singapore, where he worked on the development of proton beam writing for photonic applications. Upon joining the NTU as a Lecturer in 2005, he switched to the more exciting field of femtosecond time-resolved spectroscopy and established the xC-Lab research group – a lab for the investigation of exCited-state phenomena. His research focuses on investigating light-matter interactions, energy and charge transfer mechanisms, and probing carrier and quasi-particle dynamics in a broad range of emergent nanoscale and light harvesting systems.Dr. Nripan Mathews is an Assistant Professor at the School of Materials Engineering, Nanyang Technological University (NTU). He pursued his PhD at a joint Commissariat à l’énergie atomique (CEA) – Centre national de la recherche scientifique (CNRS) – Université Pierre et Marie Curie (Paris VI University) laboratory, where he studied the signatures of optical excitations within molecular crystals (2008). He was also a visiting researcher at Prof. Michael Graetzel’s laboratory at École Polytechnique Fédérale de Lausanne (EPFL), where he participated in a pan-European project on photoelectrochemical hydrogen production. His research focuses on a wide variety of novel materials (metal oxides, organic semiconductors, graphene, carbon nanotubes, sulfides, selenides) and novel morphologies (one-dimensional structures such as nanowires and nanotubes, thin films, and two-dimensional nanosheets) produced by a range of fabrication techniques. He has primarily investigated the electronic and optical properties of these materials and how they can be adapted for practical applications

Contents 6
About the Authors 8
Abstract 10
1 Introduction 11
1.1 Organic Photovoltaics: Background 11
1.2 Materials: Conjugated Polymers 12
1.3 Operation Principles and Physical Insights in Organic Solar Cells (OSCs) 13
1.4 Organic Solar Cell Architectures 16
1.5 State-of-the-Art, Challenges and Opportunities in OSCs 19
1.6 Surface Plasmons for Improving Light Harvesting Efficiency 20
1.7 Other Contributions to Organic Photovoltaic Performance Improvement 25
1.8 State-of-the-Art and Challenges in Plasmonic Organic Solar Cells 26
References 27
2 Surface Plasmon Resonance 34
2.1 Introduction 34
2.2 Surface Plasmon Polariton 34
2.3 Localized Surface Plasmon Resonance 37
2.4 Summary 39
References 39
3 Characterization Plasmonic Organic Photovoltaic Devices 41
3.1 Introduction 41
3.2 Optical Spectroscopy 41
3.2.1 Steady-State and Transient Absorption Spectroscopies 41
3.2.2 Time-Integrated Photoluminescence and Time-Resolved Photoluminescence 45
3.2.3 Spatially Resolved Spectroscopy 47
3.3 Electrical Characterization 47
3.3.1 Current Voltage (I-V) Measurement 47
3.3.2 Internal Photon to Current Efficiency (IPCE) Measurement 48
3.4 Numerical Simulation 48
3.4.1 Optical Simulation 49
3.4.2 Electrical Simulation 50
3.5 Summary 53
References 54
4 Plasmonic Entities within the Charge Transporting Layer 55
4.1 Introduction 55
4.2 Case Study (1): Silver Nano-Triangle Arrays in PEDOT:PSS 57
4.3 Case Study (2): Gold Nanowire Network in PEDOT:PSS 66
4.4 Case Study (3): Single Silver Nanowire in PEDOT:PSS 75
4.5 Summary and Conclusions 84
References 84
5 Plasmonic Entities within the Active Layer 89
5.1 Introduction 89
5.2 Experimental Details 91
5.3 Results and Discussion 92
5.4 Summary and Conclusions 106
References 106
6 Concluding Remarks 109
6.1 Implications for the Design of Hybrid Plasmonic OPV Devices 109
6.2 Summary and Outlook 110
References 113