Enhancement of Photoluminescence Intensity of CdSe Nanorods Doped in Cholesteric Liquid Crystals

The enhancement of photoluminescence (PL) signals of CdSe nanorods caused by embedding in the cholesteric liquid crystals (CLCs) is demonstrated in this article. Three kinds of different CLCs have been used in this experiment, and the results have shown that the phenomenon of PL enhancement generally occurs in each sample. Moreover, the relations between the enhancement and the pitch of CLCs have been analyzed as well. It displays an inversely proportional property, that is, a greater enhancement of the PL signal is achieved in the samples with shorter pitches of CLCs. The highest PL amplification acquired in this study is 3.31 times. The enhancement phenomenon is attributed to the presence of oily streaks in CLCs, which possess advantages due to the excitation of CdSe nanorods. With the versatile properties that CLC have, this study suggests that the method could provide a potential way for PL signal manipulation in many optical fields.