This lecture covers the principles and technologies behind advanced solar cells, focusing on second and third-generation photovoltaics. Topics include drawbacks of first-generation solar cells, multi-junction cells, dye-sensitized solar cells, and mesoporous titanium dioxide. The instructor discusses the history of solar cell development, from liquid junction photogalvanic cells to dye-sensitized nanostructured photoanodes. The lecture also explores the efficiency and cost-effectiveness of different solar cell technologies, such as thin-film heterojunction cells and mesoporous titanium dioxide structures.