Fast, sensitive and low-cost chemical sensor based on manufacturing nanostructured Co3O4 using Raman Spectroscopy

Abstract

Nanostructured Co3O4 has novel properties, so it can be manufactured with simple, fast preparation of samples, and a low-cost process. FESEM field emission electron microscope scanning, XRD diffraction, and Raman spectroscopy characterized Co3O4 nanostructured tetrahedral structures with multiple branches. Good sensitivity and selectivity and high stability can be seen for the nanostructured Co3O4. Cationic surfactant (CTAB) and anionic surfactant (PVP) both have a guiding effect on Co3O4 production. The self-assembled Co3O4 particles in Methylene Blue (MB) exhibit excellent Surface Enhanced Raman Spectroscopy efficiency. An average enhancement factor (EF) of 50 × 106 was achieved for the Co3O4 in PVP on 135 gsm printing paper and 41 ×106 for the Co3O4 in CTAB on 240 gsm printing paper.The results showed Co3O4 in PVP produced the highest sensitivity, specificity, and the lowest limit of detection LOD which was 0.52 nM for MB as Raman reporter molecule, and the sensitivity offered almost 98% with selectivity equal to 92%. To the best of the author’s knowledge, this is the first demonstration of Co3O4 in PVP paper-based as a chemical sensor by enhanced Raman spectroscopy signal.