Array of CdSe QD-Sensitized ZnO Nanorods Serves as Photoanode for Water Splitting

Aqueous chemically grown ZnO nanorods (NRs) arrays were sensitized by CdSe quantum dots (QDs) and were investigated as photoanode for photoelectrochemical water splitting under visible light (>420 nm) illumination. Significant enhancement of the factors 1.6 and 6 was observed for CdSe (QD)-sensitized nonannealed and annealed samples of ZnO NRs over pristine ZnO NRs arrays, respectively. The highest photocurrent density of 2.48 mA/ cm2 was registered for the annealed CdSe (QD)/ZnO (NR) arrays films at zero applied voltage and 100 mW/ cm2 (AM 1.5 G, Air Mass 1.5 Global) power density and their corresponding photocurrent density for pristine ZnO NR array was recorded as 0.41 mA/ cm2. © 2010 The Electrochemical Society.