Origin of the Raman mode in nanocrystalline zinc oxide in the vicinity of A(1) (LO) phonon mode induced by energetic heavy ions is reported. The evolution of this mode in the irradiated films is ascribed to the effect of disorder and the high density of lattice defects induced by irradiation. The presence of such defects is confirmed by the reduction in the intensity of E(2) (high) mode and band bending of the near band edge absorption. A softening of the evolved Raman mode with increasing in ion fluence is also observed. This softening cannot be attributed to spatial confinement of phonons, as the sizes of the crystallites are large. Therefore, it is explained in terms of the combined effects of phonon localization by lattice defects and the structural strain in the lattice induced by electronic energy loss transferred by energetic heavy ions

White light emission across the extended visible region of the electromagnetic spectrum from the ZnO–porous silicon (PS) nanocomposite is reported. Nanocrystallites of ZnO were grown inside the spongy structures of PS by the chemical route of sol–gel spin coating. The property of the material arises from versatile interactions among the host structures of PS and ZnO. The origin of the observed extended white light emission from 1.4 to 3.3 eV is discussed by developing a flat band energy diagram.

In the present work, shifting of Fermi level of MoS2 nanosheets due to decoration of Au nanoparticles (Au NPs) is reported. Au NPs are grown on MoS2 nanosheets by chemical reduction method. The structural analysis of pristine MoS2 and Au NPs decorated MoS2 has been done using X-ray diffraction and transmission electron microscopy. The effect of Au NPs decoration on the Fermi energy level of MoS2 nanosheets have been monitored by scanning Kelvin probe microscopy, which measures the work function in terms of contact potential difference. The work function of pristine MoS2 is found to be 4.994 eV, and it increases linearly for Au-MoS2 with increasing concentration of Au NPs. The gradual increase in the work function values indicate a systematic shifting of Fermi energy level of MoS2 towards valence band due to decoration of Au NPs.

Ion implantation technique can resolve the stability issue of metal nanoparticles with liquid iodine-based electrolyte to improve PCE of plasmonic dye-sensitized solar cells.

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