Sensitizer dyes for efficient hydrogen photoproduction

Solar energy could supply the future energy needs of a growing world population without causing the global changes associated with carbon-based energy sources. A fuel-based alternative to the direct generation of electricity is to use solar power to produce hydrogen which can be used in fuel cells or direct combustion. Using solar energy to produce hydrogen would decouple the hydrogen industry from fossil fuels. The efficient production of hydrogen using a Gratzel-based photoelectode requires a sensitizer dye capable of injecting electrons into the conduction band of semiconductors that is more negative than that of TiO ₂. The synthesis of some derivatives of silicon phthalocyanine and naphthalocyanine dyes with the required excited state reduction potential for the photoproduction of hydrogen will be presented.