Au and NiO nanoparticles dispersed inside porous SiO2 sol-gel film: correlation between localized surface plasmon resonance and structure upon thermal annealing

The favorable lattice matching between Au and NiO crystals made possible the growth of unique cookie-like nanoparticles (25 nm mean diameter) inside a porous SiO 2 film after annealing at 700\ub0C. The unusual aggregates result from the coupling of well distinguishable Au and NiO hemispheres, which respectively face each other through the (100) and (200) lattice planes. The thermal evolution of the Au and NiO nanoparticles structure has been studied by high resolution transmission electron microscopy and UV-visible absorption spectroscopy and correlated with the evolution of the Au surface plasmon resonance peak