Nanoscale synthesis and optical features of metallic nickel nanoparticles by wet chemical approaches

Highlights: → Spherical nickel nanoparticles deposited on ITO surface were successfully prepared by using a wet chemical solution method. → For the first time we realized in situ attaching Ni-NPs on ITO substrate. → All the absorption spectra present an absorption edge at 374-422 nm range corresponding to the surface plasmon resonance of Ni. - Abstract: Nickel nanoparticles (Ni-NPs) were successfully synthesized and attached on indium tin oxide (ITO) substrate by two different methods: from solution reduction process by using sodium borohydride (NaBH4) as reducing agent in the presence of poly(N-vinilpyrrolidone) (PVP) as protective and stabilizing agents and by polyol process under ethylene glycol EG as a solvent. The results indicated that the samples prepared in aqueous solution show the occurrence of face-centered cubic metallic nickel nanoparticles with a medium diameter of ∼31 nm and good size dispersion compared to the preparation in EG that revealed large size ∼150 nm. The dynamics of the nanoparticle's growth in the solvents and comparison with optical absorption is presented.