NANOSTRUCTURED PHOTOELECTRODES FOR SOLAR POWERED APPLICATIONS

Efficient, cost-effective conversion of solar energy into electrical or stored chemical energy has been a decades long ambition of scientists and engineers. Recent advances in nanotechnology have resulted in new material architectures potentially capable of achieving significant photoconversion efficiencies from easily fabricated devices of low cost. We consider solar energy conversion devices comprised of n-type TiO₂ nanotube arrays; the 1-D nanotube array geometry offers a high surface area anode with facile charge separation and directed charge transport. The TiO₂ nanotube arrays have been used successfully as the electron transporting backbone of exciton solar cells, and in combination with co-catalyst nanoparticles a photocatalytic material architecture well suited for water photoelectrolysis as well as CO₂ reduction. We consider the nanoscale design of the nanotube array structure, and its application to the conversion of solar energy into both electricity and fuel.