Stability of Photoactive Oxide Semiconductors

Zn x Cd 1-x Se quantum dot-sensitized TiO 2 nanotube (TiO 2 NT) array photoelectrodes were synthesized employing successive ionic layer adsorption and reaction (SILAR) technique. The influence of the number of deposition cycles and post-deposition annealing temperature on photoelectrochemical properties and stability behavior of photoanodes was investigated. The photoanodes were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques. Photoelectrochemical measurements indicated that TiO 2 NTs coupled with ZnCdSe quantum dots synthesized with 7 SILAR cycles, annealed at 400 o C for 1hr under N 2 atmosphere exhibited excellent photoelectrochemical properties. The high and stable photocurrent produced demonstrates the potential of Zn x Cd 1-x Se/TiO 2 heterostructure as an efficient photoanode.