Tunable, Highly Ordered TiO2 Nanotube Arrays on Indium Tin Oxide Coated PET for Flexible Bio-sensitized Solar Cells.

摘要

Highly ordered, free-standing titanium dioxide (TiO2) nanotube (TNT) arrays have been of intense interest in the alternative energies field in recent years due to their barrier-free electron conduction pathway versus TiO2 nanoparticles in dye sensitized solar cell (DSSC) designs. TNT arrays prepared by electrochemical anodization of titanium (Ti) foils and combined with a transparent, indium tin dioxide coated polyethylene terephthalate (PET) film are attractive candidates for efficient, flexible DSSCs. Flexible solar cells offer great benefits because of the potential for low-cost, roll-to-roll production and the increase in applications due to superior robustness. This approach uses a two-step anodization procedure coupled with implementation of a rapid inert gas dehydration and ultrasonic agitation detachment method. By controlling the reaction conditions during anodization (voltage, duration, and concentration), TNT arrays with specific morphology, lengths, and diameters can be tailored to satisfy a particular application such as incorporating specialized protein dyes, in particular, bacteriorhodopsin (bR). The free- standing arrays, comprised of hexagonally closed-packed and regularly ordered TNT membranes, have been synthesized and detached from the original Ti substrate. Once the TiO2 sol-gel is created, the free-standing arrays will be attached to the flexible PET film for improved photovoltaic properties and overall performance.