β-NiS and Ni3S4 nanostructures: Fabrication and characterization

Nickel sulfide nanostructures have been successfully prepared with two different sulfur sources like thiourea (S=C(NH2)(2)) and sodium sulfide by the successive ionic layer adsorption and reaction (SILAR) method. The functionalized nitrile-butadiene rubber (F-NBR) was used as stabilizing agent for formation of nickel sulfide semiconductor nanoparticles. The nanoparticle sizes correspond to 8.5 nm and 7 nm using thiourea and sodium sulfide respectively. The as-synthesized NiS and Ni3S4 nanostructures were characterized by XRD, SEM, EDX, UV vis and FTIR spectroscopy methods. A systematic investigation of the final end products has been done to elucidate the formation mechanism at different experimental parameters. Using thiourea the optical band gap of NiS for 4, 6 and 8 cycles were determined to be 3.12, 2.93 and 2.81 eV, respectively. The optical band gap of Ni3S4 for 6 and 8 cycles were determined to be 2.8 and 2.15 eV, respectively. (C) 2015 Elsevier Ltd. All rights reserved.