Concerns over pollution, climate change and sustainability of our fossil based energy sources have motivated the move towards renewable sources. In the area of alternative energy, solar energy remains to be the most ready form due to its immediateness and abundance. It is estimated that the annual global energy consumption can be met by merely covering 0.1% of the Earth’s surface with 10% efficient solar cells. The large scale adoption of photovoltaic technologies still awaits improvements in life cycle cost and long-term material performance. In these regards we have pioneered the development of highly efficient solid-state dye-sensitized solar cells (DSSC) using polymeric hole transporting materials (HTMs) such as poly(3-hexylthiophene) (P3HT) and poly(3,4-ethylenedioxythiophene (PEDOT). We have developed the first working flexible solid-state DSSC. We also have strong interest in the development of next generation solar cells based on perovskites. Together with our collaborators, we have developed the first perovskite device that functions without a HTM. We are currently working on the thin-film version of these solar cells.