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Updated: Apr 5, 2026
Synthesis of Ligand-free CdS Nanoparticles within a Sulfur Copolymer Matrix
Published on: May 1, 2016
Cu Doping in Ligand Free CdS Nanocrystals: Conductivity and Electronic Structure Study
G Krishnamurthy Grandhi1, K Swathi1, K S Narayan1
1†New Chemistry Unit, §Chemistry and Physics of Materials Unit, and ‡International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India.
Abstract:
Ligand-free Cu-doped CdS nanocrystals (NCs) have been synthesized to elucidate their surface electronic structure. The Cu-doped ligand-free NCs unlike their undoped counterparts are shown to be luminescent. We used this Cu-related emission as a probe to study the nature of the surface trap states that results in negligible luminescence in the undoped NCs. The concentration of the sulfide ligands is shown to play a crucial role in the surface passivation of the NCs. Electrical conductivity of these NCs was also studied, and they were shown to exhibit significant conductivity of ∼10(-4) S cm(-1). Further we have shown that the electrical conductivity is closely correlated to the surface charge and hence the trap states of the individual NCs have far-reaching consequences in the device optimization.
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