2,4-dinitrotoluene detected using portable Raman spectrometer and femtosecond laser fabricated Au–Ag nanoparticles and nanostructures

摘要: Abstract We report results from our studies on the fabrication of bimetallic nanoparticles (NPs) and nanostructures (NSs) using femtosecond ( ∼ 50 fs) laser ablation technique. The NPs NSs were achieved by immersing bulk targets with different Au–Ag compositions in acetone followed ablation. demonstrate their application towards detection an explosive molecule 2, 4-Dinitrotoluene, DNT (25 μ M) a portable Raman spectrometer (785 nm). A tuneable surface plasmon peak observed UV-Visible absorption spectra varying Au proportions confirmed formation NPs. size, shape crystallographic phases investigated transmission electron microscope (TEM) selected area diffraction pattern (SAED). morphology fabricated was characterized field emission scanning (FESEM). Both employed as Surface Enhanced Scattering (SERS) substrates for sensing Methylene Blue (MB) DNT. From obtained this investigation we concluded that Au70Ag30 NPs/NSs exhibited superior SERS performance compared to pure Ag, other compositions. limit 10−9 M MB 10 − 6  M corresponding enhancement factors 7 104. Furthermore, have also ‘factor 3’ increase intensity simply drop casting Ag gaps NSs. This clearly demonstrates individual NPs, (hybrid targets) can be single experiment combination provide efficient means detecting trace quantities molecules.