TY - BOOK

T1 - Silicon Passivation and Photosensitisation Using Organic Monolayers and Light-Harvesting Chromophores

AU - Wood, Ben

PY - 2024/10/5

Y1 - 2024/10/5

N2 - The work set out in this thesis looks to provide insights into the development of thin-film crystalline silicon photovoltaics by: i) passivation of silicon using organicmonolayers, followed by ii) photosensitisation of passivated silicon using light-harvesting complexes.Chapter 1 introduces current trends in energy and photovoltaics, with a focus onsilicon-based solar cells. This serves as the motivation for the project, as societycontinues to look for cheaper and more sustainable energy resources. Chapter 2 will introduce the key technical concepts explored in this thesis, including semiconductor physics, and the analytical methods used in this work.In chapter 3, silicon wafers are chemically passivated using wet-chemical methods. The chlorination-alkylation method is used to form self-assembled organic monolayers on the surface of silicon. The fabricated surfaces are analysed by X-ray photoelectron spectroscopy to prove successful bonding had been achieved. The samples are then analysed using photoluminescence techniques to measure the emission and decay spectra of the surfaces, indicating the quality of passivation.In chapter 4, energy transfer between light-harvesting complexes and silicon isexplored. The aforementioned passivated surfaces are further modified throughcoupling reactions in order to form a covalent tether between the silicon surface and light-harvesting complexes. Energy transfer is measured via fluorescence lifetime imaging spectroscopy.In chapter 5, the Langmuir-Blodgett technique is deployed to measure the effects of distance dependent energy transfer. Distance between silicon and light-harvesting complex can be modified by introducing layers of stearic acid spacers. Multiple layers of stearic acid are built upon the silicon to control the separation distance between complex and silicon. The fluorescence lifetimes are plotted to examine the relationship between energy transfer and distance.

AB - The work set out in this thesis looks to provide insights into the development of thin-film crystalline silicon photovoltaics by: i) passivation of silicon using organicmonolayers, followed by ii) photosensitisation of passivated silicon using light-harvesting complexes.Chapter 1 introduces current trends in energy and photovoltaics, with a focus onsilicon-based solar cells. This serves as the motivation for the project, as societycontinues to look for cheaper and more sustainable energy resources. Chapter 2 will introduce the key technical concepts explored in this thesis, including semiconductor physics, and the analytical methods used in this work.In chapter 3, silicon wafers are chemically passivated using wet-chemical methods. The chlorination-alkylation method is used to form self-assembled organic monolayers on the surface of silicon. The fabricated surfaces are analysed by X-ray photoelectron spectroscopy to prove successful bonding had been achieved. The samples are then analysed using photoluminescence techniques to measure the emission and decay spectra of the surfaces, indicating the quality of passivation.In chapter 4, energy transfer between light-harvesting complexes and silicon isexplored. The aforementioned passivated surfaces are further modified throughcoupling reactions in order to form a covalent tether between the silicon surface and light-harvesting complexes. Energy transfer is measured via fluorescence lifetime imaging spectroscopy.In chapter 5, the Langmuir-Blodgett technique is deployed to measure the effects of distance dependent energy transfer. Distance between silicon and light-harvesting complex can be modified by introducing layers of stearic acid spacers. Multiple layers of stearic acid are built upon the silicon to control the separation distance between complex and silicon. The fluorescence lifetimes are plotted to examine the relationship between energy transfer and distance.

U2 - 10.17635/lancaster/thesis/2515

DO - 10.17635/lancaster/thesis/2515

M3 - Doctoral Thesis

PB - Lancaster University

ER -