IMPROVED SURFACE ENHANCED RAMAN SCATTERING FOR NANOSTRUCTURED SILVER ON POROUS SILICON FOR ULTRASENSITIVE DETERMINATION OF 2,4,6-TRINITROTOLUENE

Label-free and low-cost surface-enhanced Raman scattering-active substrates of silver nanostructures on porous silicon have been synthesized. The morphology and spectroscopic properties were investigated as a function of concentration and immersion time. The enhancement factor of optimized silver-porous silicon substrate was estimated to be 2.18x10(8) by the use of p-thiocresol as a Raman probe. The optimized substrate was used to determine 50pg of 2,4,6-trinitrotoluene. These results demonstrate that the prepared silver-porous silicon substrates are promising for the ultra-sensitive determination of organic molecules.