Vol. 7, Issue 2, Part D (2025)

Nickle Sulfide (NiS) nanocrystals of different shapes are synthesized by a one pot hydrothermal process using polyacrylamide (PAM) as surfactant and thiourea as the source of sulphur. The nanocrystals grow from nanoparticle decorated along the PAM chain to NiS nanoflakes. However, the nanoflakes get agglomerated when the hydrothermal temperature (TH) is further increased due to van der waals forces and magnetic attractions. As grown NiS nanocrystals are characterized by XRD, FTIR, TGA, FE-SEM, TEM, UV-Vis. absorption spectroscopy and photoluminescence (PL) spectra. XRD reveals the crystallinity of the NiS, whereas SEM demonstrates the gradual change in morphology of the NiS. However, UV-Vis. absorption and PL spectra shows that the optical spectra of the NiS is due to various defect states.