Tunable TiO_2 Nanotube Arrays for Flexible Bio-Sensitized Solar Cells

摘要

Highly ordered, free-standing titanium dioxide nanotube (TiNT) arrays have been of intense interest to the alternative energies field in recent years due to their barrier-free electron conduction pathway vs. TiO_2 nanoparticles in dye-sensitized solar cell (DSSC) designs. TiNT arrays prepared by electrochemical anodization of Ti foils and combined with a transparent, Indium Tin Dioxide coated PET film are attractive candidates for efficient, flexible DSSC's. 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 utilizes 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, concentration), TiNT arrays with specific morphology, lengths, and diameters can be tailored to satisfy a particular application such as incorporating specialized protein dyes-in particular, bacteriorhodopsin. The free-standing arrays comprised of hexagonally closed-packed and regularly ordered TiNT membranes have been synthesized and detached from the original Ti substrate. Once the TiO_2 sol-gel is created, the free-standing arrays will be attached to the flexible PET film for improved photovoltaic properties and overall performance.