Study of optical and electrical properties of water-soluble conjugated poly(3-hexylthiophene) on different grain-sized mesoporous TiO2 layers

Solid-state hybrid solar cells are promising candidates for future low-cost photovoltaic energy generation that are based on polymer/metal oxide donor/acceptor heterojunctions. However, a critical drawback of hybrid solar cells is the usage of toxic and environmental unfriendly organic solvents in the phase of preparation. In terms of environmental impact, “green” and safer materials are required towards processing of eco-friendly hybrid solar cells. In this work, during processing phase of eco-friendly hybrid solar cells, aqueous-soluble conjugated poly(3-hexylthiophene) material is used as photo-active and hole transporting layer and TiO2 layer as electron accepting layer. Optical, topographical and morphological characterizations on different grain-sized TiO2 layers with polymer films are studied. The influence of eco-friendly hybrid solar cell electrical properties in combination with different grain-sized TiO2 layers measured under N2 and ambient conditions are discussed. It is important to understand these properties for further optimizations.