Influence of starch capping effect on optical absorption and photoluminescence behaviour of ZnS nanoparticles

[Display omitted] •Starch capped ZnS nanoparticles were synthesized using chemical precipitation method.•The cubic ZnS structures with spherical morphology was observed.•The PL quenching addressed as a function of starch concentration. The green chemical of route synthesis followed and the precursor compounds taken during the synthesis of ZnS nanoparticles (NPs) play an imperative role on their structural and photo physical properties. The green chemical route of synthesis of NPs is proved to be an advantageous method imparting novel properties to the synthesized NPs. Present study involves the synthesis of uncapped and starch capped ZnS NPs by a facile chemical coprecipitation technique. ZnS NPs have been synthesized using zinc acetate and sodium sulfide as precursors. The structural and morphological features of the samples were studied by X-ray diffraction (XRD) and field emission electron microscopy (FESEM). Fourier transform infra red spectra (FTIR) was carried out to confirm capping by starch. Compositional analysis was done by electron dispersive spectroscopy (EDS). Optical properties were analyzed using UV-absorption spectra and photoluminescence (PL) measurements. Formation of ZnS NPs with cubic phase was revealed by XRD and quantum confinement effect by the UV absorption. With increase in capping agent (starch) concentration PL intensity decreased. Such heavy metal free, nontoxic ZnS nanoparticles are suitable for optoelectronic applications.