Cadmium sulphide quantum dots with tunable electronic properties by bacterial precipitation.

ABSTRACT: We present a new method to fabricate semiconducting, transition metal nanoparticles (NPs) with tunable bandgap energies using engineered Escherichia coli. These bacteria overexpress the Treponema denticola cysteine desulfhydrase gene to facilitate precipitation of cadmium sulphide (CdS) NPs. Analysis with transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy reveal that the bacterially precipitated NPs are agglomerates of mostly quantum dots, with diameters that can range from 3 to 15 nm, embedded in a carbon-rich matrix. Additionally, conditions for bacterial CdS precipitation can be tuned to produce NPs with bandgap energies that range from quantum-confined to bulk CdS. Furthermore, inducing precipitation at different stages of bacterial

SUBMITTER: Marusak KE 

PROVIDER: S-EPMC5397112 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature