Mercury Detection with Ag Nanoparticles Reduced on Si Thin Films

Abstract

AbstractA surface plasmon resonance mercury sensor was demonstrated by electroless reduction of silver nanoparticles on amorphous silicon thin films. Unlike the previous Ag/Au nanoparticle - Hg interaction investigations, which monitored the blue shift of the dipolar plasmon band of well-dispersed nanoparticles, the present work reveals and explores the red shift of the symmetric hybrid plasmon mode of the interacting nanoparticles in response to Hg vapor exposure. Sensitivity to Hg was explored with varying nanoparticle size, which could be controlled by the immersion time associated with the reduction process. The recovery of the hybrid plasmon band after the Hg exposure was also monitored which was observed to be slower than the recovery of the dipolar plasmon band for noninteracting particles.