Photoluminescence study of Au-Ag bimetallic nanoparticles supported on mesoporous silica SBA-15

Bimetallic au-ag nanoparticles with homogeneous dispersion in amine-modified sba-15 mesoporous silica channels were successfully synthesized by the post-modification method. the obtained nanocomposites with different component ratios were studied by structural, physico-chemical ,and optical analysis. the structural and physico-chemical properties were studied by x-ray diffraction (xrd), transmission electron microscopy (tem), fourier transform infrared (ftir) spectroscopy, and nitrogen adsorption-desorption isotherm measurement (bet). the optical properties were characterized by photoluminescence (pl) and uv-vis spectroscopy. the photoluminescence and absorption spectra were strongly affected by the change in the compositional ratio of gold to silver nanoparticles due to the interactions of au-ag nanoparticles, the configuration of conduction electrons, and their plasmonic properties. a significant enhancement was observed in the photoluminescence spectrum in the long-wavelength red emission at 640 nm for a one-to-one composition ratio of au/ag/sba-15 nanocomposite. since the light emission of most microorganisms is in the visible range, the nanocomposite produced can be proposed for applications in biosensor technology.