Enhancement in the Photorefractive Performance of Organic Composites Photosensitized with Functionalized CdSe Quantum Dots
Enhancement in the photorefractive (PR) performance of organic composites photosensitized by CdSe quantum dots (QCdSe) passivated with the charge-transport ligands, sulfonated triphenyldiamine (STPD), is reported. This enhancement is primarily attributed to the ability of the passivating ligand, STPD, to facilitate the charge-transfer process between the QCdSe and the triphenyldiamine (TPD) charge-transport matrix. The PR composites exhibited a maximum photocharge-generation efficiency of 0.9% and two-beam coupling gain coefficient of 110 cm-1. These figures of merit represent a significant improvement over similar composites photosensitized with more conventional trioctylphosphine oxide-passivated QCdSe (TQCdSe). Moreover, composites photosensitized with SQCdSe had a faster response time of Ï" = 128 ms at an electric field of 60 V/µm compared with Ï" = 982 ms for those containing TQCdSe. Because of the molecular similarity between the STPD passivating groups and the TPD-based charge-transport matrix, concentrations of up to 1.4 wt% of SQCdSe are achieved in PR composites without any detectable phase separation, a considerable improvement over the 0.7 wt% for TQCdSe.
Y. Liang et al., "Enhancement in the Photorefractive Performance of Organic Composites Photosensitized with Functionalized CdSe Quantum Dots," Optical Materials, vol. 58, pp. 203-209, Elsevier B.V., Aug 2016.
The definitive version is available at https://doi.org/10.1016/j.optmat.2016.05.040
Keywords and Phrases
Photorefractive; Quantum dots; Triphenyldiamine
International Standard Serial Number (ISSN)
Article - Journal
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