Microbe-Assisted Synthesis and Luminescence Properties of Monodispersed Tb3+-Doped ZnS Nanocrystals

Abstract EN

Tb3+-doped zinc sulfide (ZnS:Tb3+) nanocrystals were synthesized by spray precipitation with sulfate-reducing bacterial (SRB) culture at room temperature.

The morphology of the SRB and ZnS:Tb3+ nanocrystals was examined by scanning electron microscopy, and the ZnS:Tb3+ nanocrystals were characterized by X-ray diffractometry and photoluminescence (PL) spectroscopy.

The PL mechanism of ZnS:Tb3+ nanocrystals was further analyzed, and the effects of Tb3+ ion concentration on the luminescence properties of ZnS:Tb3+ nanocrystals were studied.

ZnS:Tb3+ nanocrystals showed a sphalerite phase, and the prepared ZnS:Tb3+ nanocrystals had high luminescence intensity under excitation at 369 nm.

The main peak position of the absorption spectra positively blueshifted with increasing concentrations of Tb3+ dopant.

Based on the strength of the peak of the excitation and emission spectra, we inferred that the optimum concentration of the Tb3+ dopant is 5 mol%.

Four main emission peaks were obtained under excitation at 369 nm:489 nm (5D4→7F6), 545 nm (5D4→7F5), 594 nm (5D4→7F4), and 625 nm (5D4→7F3).

Our findings suggest that nanocrystals have potential applications in photoelectronic devices and biomarkers.