Surface plasmonic resonances and enhanced IR spectra in GZO nano-triangle arrays

• GZO nano-triangle arrays were fabricated by NSL and PLD techniques.
• The SPR peaks of GZO arrays were tuned by changing doping concentration.
• Absorption peaks of PMMA were enhanced by GZO nano-triangle arrays.

Ga-doped zinc oxide (GZO) nano-triangle arrays with different doping concentration and sizes were fabricated by nanosphere lithography (NSL) and pulsed laser deposition (PLD) techniques, using GZO targets and polystyrene (PS) spheres. The influences of doping concentration on band gap and optical properties were investigated using ultraviolet-visible spectra and Fourier transform infrared (FTIR) spectra. The surface plasmonic resonance (SPR) peaks of the GZO nano-triangle arrays could be tuned in infrared region by changing the doping concentration. The surface-enhanced infrared spectroscopy (SEIRS) experiments of polymethyl methacrylate (PMMA) films on GZO nano-triangle arrays indicated that the absorption peaks of the PMMA overlapped with the SPR peaks of GZO nano-triangle arrays (on-resonance) could be enhanced. However, the off-resonance peaks of the PMMA could not be enhanced.