Abstract. Spindle-shaped CuS nanoparticles of sizes 3-13 nm dispersed in starch were synthesized using copper acetate monohydrate (Cu(CH₃COO)₂) and thiourea (SC(NH2)2) as precursors via a green biocompatible chemical route. The structure indicated a possible phase change from covellite to djurleite under different growth conditions. Absorption spectra showed good quantum confinement of CuS in starch matrix with an enhancement of the band gap 2.8-3.85 eV. The photoluminescence (PL) spectra exhibited a strong UV-Vis.-blue emission in the ranges 362-395 nm and 398-471 nm with excitation wavelengths of 325 nm and 350 nm respectively along with some weak green emissions. Ionic contributions of the electrolytic ionic CuS solution as measured by a standard conductivity cell clearly showed the semiconducting behavior of the product material. The activation energies were in the range 0.1007-0.1602 eV. The ionic properties of the ionic CuS solution were correlated with molar concentration of the host material. Studies have shown that ionic CuS solutions behave as weak electrolytes dispersed in starch and may be potentially exploited as mixed ionic electronic conductors in electrochemical technology. The excellent optoelectronic properties of the as synthesized material may also be utilized in different optoelectronic devices such as UV-Blue LEDs.

doi: https://doi.org/10.55318/bgjp.2023.50.3.280

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