6. Summary

In summary, this chapter aimed at recognizing and highlighting various approaches to modify TiO2 material based on the studies focusing on dye-sensitized solar cells. The emphasis was to identify the most successful examples and to rationalize their effect in enhancing electronic mobility, charge carrier generation and diffusion, conduction band shift, surface passivation, light harvesting, long term stability and ease of application. In general, TiO2 modification can be categorized into hard modification and soft modification. Hard modification involves the addition of moieties such as plasmonic nanostructures, metal oxides, and morphological variations during synthesis such as a high temperature sintering (400–500C) step is required to achieve required functionality. On the other hand, soft modification (simple rinse and dry) post sintering surface treatment with additives, co-adsorbents, and electrolyte additives is rather simple to apply. With the discussion and literature provided in the chapter we hope the state of knowledge learned from dye-sensitized solar cells will benefit the scientific community to expand on the functionality of TiO2 as it is being applied and explored in the fields of energy storage (batteries, super capacitors), photocatalysis, PVs, and sensors.
