Effect of spectral overlap and mixing ratio on metal-semiconductor mixed colloid

Abstract

Abstract Metal-semiconductor hybrid colloid is an emerging paradigm for the construction of advanced materials having multiple functionalities. In such colloids, the ratio between the number of metal nanoparticles (NP) to the number of semiconductor quantum dots (QD) plays an important role in controlling the properties of the final hybrid colloid. We study the effect of the mixing ratio of Ag NPs to the CdTe QDs on the photoluminescence (PL) properties of the final mixed hybrid colloid. Using steady-state and time-resolved photoluminescence, it has been shown that when exciton and plasmon spectrally overlap in a hybrid, the amplitude of the decay component of PL depends on the excitation energy. Such dependence is not observed in the case of hybrid where exciton and plasmon are spectrally separated. This study contributes to the appropriate selection of the shape of metal NPs in designing a hybrid material that is well suited for optoelectronic device applications.