Fig. 2
From: Modulation of nanoparticle separation by initial contact angle in coffee ring effect
a Schematic of PDMS-coated glass by PDMS stamp. b Image of patterned droplet on PDMS coated glass. c Contact angle of droplet vs. time after PDMS stamping. d SEM image of contact line of evaporated droplet with 100 nm, 500 nm, and 1 µm beads on PDMS-coated glass. AFM image of e PDMS coated area on glass and f non-coated glass. Surface roughness of g PDMS coated glass and h untreated glass