Detection of heavy metal compounds using a novel inkjet printed surface enhanced Raman spectroscopy (SERS) substrate

A novel surface enhanced Raman spectroscopy (SERS) substrate was successfully fabricated on a silicon wafer using inkjet printing. Silver (Ag) nanoparticle (NP) based ink, with average particle size of 150 nm, was inkjet printed on the surface of the silicon wafer. A thickness of 400 nm was measured for the printed Ag NP film using vertical scanning interferometry. The Ag NP printed SERS substrate was tested toward heavy metal compounds like cadmium sulfide (CdS), zinc oxide (ZnO) and mercury sulfide (HgS). An amplification of the SERS intensity by an order of 3–5 times was observed for all test samples, due to the presence of hotspots between the metal nanoparticle aggregates. The responses demonstrated the feasibility of the novel SERS substrate to be used in applications for detection of heavy metal compounds.