Figure 1: Advanced localized collection and spotting of airborne species for gas sensor applications. | Nature Communications

Figure 1: Advanced localized collection and spotting of airborne species for gas sensor applications.

From: Effective localized collection and identification of airborne species through electrodynamic precipitation and SERS-based detection

Figure 1

(a,b) A nanostructured substrate commonly used in SERS called AgFON, which uses Ag-coated SiO2 beads14,22; in a collection is driven by diffusion; in b collection is driven by basic electrostatic precipitation through application of a bias voltage, where Id reflects the rate of charge dissipation. (c) The concept of electrostatic precipitation is enhanced using an electrodynamic nanolens approach; a nanolens is formed using a patterned photoresist layer (PR) to funnel, concentrate, and spot the molecules at predetermined locations while preventing deposition on the positively charged resist. (d) The concept is further enhanced using electrically separated domains to receive different analytes at different times; domains are programmed by applying an external bias voltage. Inserts in c and d depict scanning electron microscope and optical microscope images of the corresponding test structures and dimensions that were used. (c,d) Scale bar, 20 μm; (c, inset), 700 nm.

Back to article page