The world is facing big challenges related to the energy issues. The demand is increasing day by day. Third world countries are facing loading shedding which is only due to the less production and more consumption of energy. Most of the sources, techniques and ways to produce energy have a lot of issues e.g. expensive, environmental concerns, stability etc. Among all sources the photovoltaic technology is good one. Moreover, dye-sensitized solar cells (DSSCs) are gaining attention due to the environmental friendly, cheap, easy to fabricate but these are still in the early stages. This book would be helpful to educate towards alternative energy sources. Additionally, these energy sources would be pollution free as compared to coal which is a source of electricity Triphenylamines are the stable organic chromophores which showed the efficiency 9% in some studies and the properties can be tuned by push-pull and bridge elongation strategies. The present book deals with the Structural, electronic, optical properties and electron injection as well as structure-property relationship.