Free-Standing TiO2 Nanotube Arrays for Front-Side Illuminated CdS Quantum Dots Sensitized Solar Cells

Front-side illuminated CdS quantum dots (QDs) sensitized solar cells (QDSSCs) based on TiO2 nanotube arrays (TNTAs) were fabricated. The free-standing TNTAs (f-TNTAs) membranes were obtained from anodic oxidized Ti foils by self-detaching technique and then transferred to FTO glass substrates to form photoanodes. CdS QDs were loaded on TNTAs by sequential chemical bath deposition approach. Scanning electron microscope (SEM) results indicated that the morphology and structure of TNTAs membranes did not change in detaching and transferring process. Power conversion efficiency of the devices from the front-side illumination mode is 1.47 %, which is much higher than that (0.34 %) of the back-side illumination mode owing to the markedly improved light absorption.