Templet-free one-pot synthesis of Bi-doped ZnTe nanoflowers by cation exchange method for optoelectronic applications and antibacterial activity

Abstract

The present report investigates the preparation of Bi-doped ZnTe (Bi:ZnTe) nanosheets (NS) with a variation in Bi contents for different optoelectronic applications and antibacterial responses. A flower-like Bi:ZnTe NS assemblies were synthesized by a cation exchange reaction, where the average thickness of the individual NS was found to be in the range of 20–30 nm. The average thickness of the NS gradually increases with an increase in the Bi concentration. The obtained NS shows high crystallinity properties with a hexagonal ZnTe phase. With the increase in the Bi concentration, there is no significant change in either crystallinity or the phase of the NS observed. The optical properties of the as-synthesized Bi:ZnTe NS were analyzed through the UV-Vis absorbance spectra, where a variation in the absorption edge with a change in the Bi content is apparent. The optical bandgap of the material gradually increases with an increment in the Bi concentration. The photoluminescence (PL) measurement was carried out to analyze the applicability of the NS for different optoelectronic applications. Broad PL spectra for different Bi:ZnTe NS are obtained in the 520–850 nm range, with the peak around 600 nm for 532 nm excitation. Due to the non-toxic nature of the constituent elements, the Bi:ZnTe NS is favorable for biological applications. The antibacterial activities of the Bi:ZnTe NS against two pathogenic bacteria are examined, where a good antibacterial response is observed.