Effect of nanoparticle shape on the conductivity of Ag nanoparticle poly(vinyl alcohol) composite films

In this work, the shape effect of silver nanoparticles (AgNPs) on photocatalysis and electrical conductivity was investigated. Different shapes of AgNPs achieved using various concentrations of NaBH 4 were characterized using particle size analysis, UV–visible spectroscopy and high‐resolution transmission electron microscopy. The colours of colloidal solutions were found to be influenced by the shape of the nanoparticles. Yellow and blue AgNPs were spherical and triangular in shape, respectively, whereas distorted spherical particles showed a red colour and the presence of both particles in one solution resulted in a green colloidal solution. The AgNPs were used to prepare Ag/poly(vinyl alcohol) (PVA) composite films and their electrical conductivity was investigated. Owing to their better charge carrier generation, uniform distribution in the PVA matrix and enhanced surface plasmon resonance, blue AgNPs (triangular shaped) exhibited superior conductivity performance compared to the other nanoparticles. The values for maximum conductivity for the blue and yellow AgNPs were 3.45 × 10 −4 Ω −1 cm −1 and 2.67 × 10 −4 Ω −1 cm −1 respectively.