CdSe quantum dots (QDs) of different sizes have been deposited on graphene oxide (GO) films on conducting glass electrodes. Electron transfer rates from photoexcited CdSe QDs to GO were found to be dependent on QD particle size. Smallest QDs with more negative conduction band potentials show around three times faster electron transfer rates than the largest QDs used. Furthermore emission quenching of colloidal CdSe QDs was found to be dependent upon the extent of reduction of GO. Electrophoretic deposition was used to deposit CdSe-GO composites in a �rainbow� fashion. Photoelectrochemical results highlight the ability to tune the photo response via size control of CdSe QDs and enhancement in photoconversion efficiency by incorporating GO which suppresses charge recombination. The onset of IPCE (Incident photon to current conversion efficiency) observed increases with QD particle size. By combining larger IPCE onset of larger particles with faster electron transfer rates of smaller ones, improved light harvesting was achieved. Additionally, incorporating GO in CdSe photo anodes was found to enhance the charge separation and improve power-conversion efficiency.

Rainbow CdSe- graphene oxide assembly: Size dependent electron transfer and enhanced light energy conversion

246th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.