MAGNETITE-SILVER DECORATED SILICA NANOFIBERS AS POTENTIAL ECONOMIC SUSTRATES FOR SURFACE-ENHANCED ABSORPTION INFRARED.

Abstract

Surface-enhanced infrared absorption spectroscopy (SEIRAS) is a powerful technique for the identification and characterization of molecules at low concentrations. However, SEIRAS amplification substrates with high performance are typically fabricated using complex techniques, which significantly increase the cost of the substrates and make the SEIRAS technique less affordable. Therefore, research efforts focus on developing cost-effective materials. In this study, the fabrication of Magnetite-Silver Decorated Silica Nanofibers SEIRAS substrates is proposed in a simple and low-cost manner using silica nanofibers decorated with magnetite and silver nanoparticles, employing sol-gel, chemical reduction, and coprecipitation techniques. Silica nanofibers were prepared via the sol-gel and electrospinning methods and were sintered to obtain high-purity silica nanofibers with an average diameter of 280 nm, as determined by IR spectroscopy and SEM studies. Magnetite nanoparticles were synthesized using the coprecipitation method, with a diameter of 35.6 nm according to DLS analysis and a crystal size of 17 nm based on XRD characterization. Silver nanoparticles were synthesized through the chemical reduction method, resulting in nanoparticles with an average diameter of 45 nm, as determined by DLS, and a maximum absorption peak at 410 nm, as shown by UV-Vis analysis. The SEIRAS substrates obtained exhibit high performance with amplification factors of 10⁵, and they enhance all vibrational modes of the analyte due to the selection rules governed by the cooperative effect of magnetic and electric fields