Investigation of graphene and tin selenide related materials for their potential application in dye sensitized solar cells on both flexible and rigid substrates
Devarepally, Kishore Kumar
MetadataShow full item record
With the growing demand for tapping renewable sources of energy, the solar energy has emerged as champion with many potential applications been developed using disruptive technologies and effective application of advancements in material science with nano approach. This thesis is a compilation of experimental studies performed to enhance the performance of dye sensitized solar cells (DSSC) using low cost, easy to synthesize, and earth abundant materials such as graphene and graphene related materials, tin selenide and its related materials. Techniques such as screen printing and doctor blade method have been explored as a part of this research. Chapter 1 deals with the introduction and comprises of a literature survey and overview of various generations of solar cells. Besides this, it also describes the working principle of dye sensitized solar cell. It also includes a discussion on various basic and applied concepts, such as solar cell device architectures, photoanode, sensitizers, and electrolyte and counter electrodes with photoconversion parameters Chapter 2 discusses the details of the optimisation of binder free TiO2 paste preparation for polymer flexible substrates. It includes the fabrication process of polymer flexible DSSC. Besides this, the challenges in flexible DSSC, TiO2 paste preparation, TiO2 film preparation and processing is also discussed. Chapter 3 discusses the synthesis of graphene quantum dots by electrochemical voltammetry technique and characterisation of graphene quantum dots by XRD, Raman spectroscopy, TEM, UV Vis. absorption, photoluminescence and life time decay. Finally, the photovoltaic performance of binder free graphene quantum dot-TiO2 photoanode for polymer flexible DSSC has been studied and results are compared with the TiO2 photoanode. Chapter 4 deals with the synthesis of graphene oxide using the modified Hummer’s method. The synthesized graphene oxide is characterized by XRD, Raman spectroscopy and XPS. The characteristic oxidation and reduction peaks of graphene oxide have been evaluated by the cyclic voltammetry. Finally, photoconversion parameters of graphene oxide as a counter electrode have been investigated and results were compared with a standard platinum counter electrode. Chapter 5 deals with the synthesis of tin selenide using the solid state method. The tin selenide films are prepared by the screen printing method and the films are characterised by XRD and SEM. The characteristic oxidation and reduction peaks of tin selenide have been evaluated by the cyclic voltammetry. Finally, photoconversion parameters of tin selenide as counter electrode have been investigated and results were compared with a standard platinum counter electrode. Chapter 6 deals with the SnSe decorated TiO2 films by successive ionic layer adsorption and reaction method. Also discusses the background introduction of quantum dots sensitization. The SnSe decorated TiO2 are characterized by XRD and SEM. Finally the J-V measurements of the SnSe QD sensitized solar cells are investigated. Finally, chapter 7 presents the major conclusions derived from the present work and the scope of the some future studies in this field.