Ligand capping effect for dye solar cells with a CdSe quantum dot sensitized ZnO nanorod photoanode

Abstract

We report a quantum dot sensitized solar cell (QDSSC) with a thioglycolic acid (TGA) capped CdSe quantum dot (QD) sensitized ZnO nanorod photoanode. As revealed by UV-Vis absorption spectrum and transmission electron microscopy, the quantum dots can be effectively adsorbed onto ZnO nanorods. By studying the emission decay, the quenching of the CdSe QDs by ZnO nanorod was verified, and an electron transfer (from QD to ZnO) rate constant of 1 x 10(8) s(-1) was obtained. The efficiency of the as-prepared QDSSC was 0.66% and an incident power conversion efficiency of 22% at 400 nm was achieved.

One-dimensional ZnO nanostructures: Solution growth and functional properties

“…The quantum dots are usually capped with ligands that can form chemical bonds with the ZnO nanowire surfaces. Therefore the ligand molecule length influences the charge transfer rate at the interface, with short chain lengths having faster transfer rates [477].…”

Photophysical properties gallium octacarboxy phthalocyanines conjugated to CdSe@ZnS quantum dots

“…Fitting of the luminescence decay curves for the QDs and the Pc-QDs conjugates (when excited where QDs absorb) resulted in three lifetimes (s F(QDs) ) as is typical of QDs [46,47]. For the same reason given for the U F values, the core shell showed longer lifetimes compared to core (considering the long lived species, Table 1).…”

Fluorescence Behaviour and Singlet Oxygen Production of Aluminium Phthalocyanine in the Presence of Upconversion Nanoparticles

“…FRET is not the only process that results in the decrease in the donor emission [41,42], hence the observed weak stimulated emission of ClAlTSPc which does not correspond to the large decrease in UCNP emission. There are many factors other than FRET reported (and are still under debate) that influence photoluminescence decrease in nanoparticles such as quantum dots (QDs) [41][42][43][44]. For example, it has been reported that for QDporphyrin nanocomposites, the major part of the observed quenching of QD photoluminescence can be assigned to non-FRET processes [44].…”

“…There are many factors other than FRET reported (and are still under debate) that influence photoluminescence decrease in nanoparticles such as quantum dots (QDs) [41][42][43][44]. For example, it has been reported that for QDporphyrin nanocomposites, the major part of the observed quenching of QD photoluminescence can be assigned to non-FRET processes [44]. As already stated, the surface properties and the crystal structure of nanocrystals can change the intensity of UCNP fluorescence peaks [45].…”