Comparative study on plasmonic properties of a Ni film and 2D Ni nanodot array fabricated on an ITO substrate

[Display omitted] •Two-dimensional Ni NDAs with diameters of 45nm and 90nm were formed on ITO substrates using anodic aluminum oxide masks.•The extinction spectrum of 50nm thick Ni film exhibited a broad dip at 437nm.•The LSPR of the Ni NDA with a 45nm diameter shows a broad peak at approximately 400nm. A two-dimensional (2D) Ni nanodot array (NDA), made of transition metals with partially filled d-bands, was fabricated on an indium tin oxide (ITO) substrate with good transparency using a porous anodic aluminum oxide mask. A Ni film with the thickness of 50nm exhibits a broad dip at 437nm in the extinction spectrum, while a Ni NDA with the diameter of 45nm shows a broad localized surface plasmon resonance (LSPR) peak at 400nm. Both the broad-shaped dip and peak are due to the surface plasmon resonance and the d-band related absorption. We confirmed that the size dependence of transition metals is weak in the LSPR spectra of Ni NDAs, with diameters of 45nm and 90nm.