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Updated: Jan 19, 2026

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
Ternary Metal Chalcogenides: Into the Exciton and Biexciton Dynamics
Tushar Debnath1, Hirendra N Ghosh1,2
1Radiation and Photochemistry Division , Bhabha Atomic Research Centre , Mumbai 400085 , India.
Abstract:
Intra-band-gap state-induced low-toxicity colloidal I-III-VI ternary metal chalcogenide nanocrystals (NCs) have emerged as promising alternatives to the toxic Cd- and Pb-chalcogenides for different optoelectronic and bioimaging applications. In this Perspective, we provide the primary understanding of the intra-band-gap state-induced photoluminescence (PL) of I-III-VI NCs, specifically CuInS2 and AgInS2, as a function of particle size and composition and correlated with time-resolved PL measurements. The intra-band-gap state-induced ultrafast exciton and biexciton dynamics are discussed in detail to unravel the subpicosecond carrier relaxation dynamics through transient absorption measurement. Furthermore, ultrafast dissociation of the biexciton on Au@CuInS2 hybrid NCs has been revealed to be due to the presence of Au, which has direct relevance to the improvement of the solar cell efficiency. The proper fundamental insight of the ultrafast exciton and biexciton dynamics of these materials will enable utilization of ternary metal chalcogenides in photovoltaic as well as light-emitting devices.
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