Self‐seeding synthesis of silver nanosheets with binary reduction in poly(vinylpyrrolidone)–sodium dodecyl sulphate aggregation microreactor

Abstract

Silver (Ag) nanosheets were synthesised through a facile self-seeding strategy with binary reduction in the poly(vinylpyrrolidone) (PVP)sodium dodecyl sulphate (SDS) aggregation microreactor, in which the size and morphology of Ag nanoparticles were able to be regulated by concentration or pH dependence. In this approach, PVP and SDS built the microreactor together and served as a synthesis template; a trace of sodium borohydride (NaBH 4) was employed to rapidly trigger the competitive formation of small Ag seeds, while PVP was responsible for the subsequent reduction and slow crystal growth. The size and morphology of the nanosheets could be gently regulated with the concentrations of PVP or SDS and the pH of the reaction solution; while the dramatic variance of size and morphology was primarily induced by NaBH 4 concentration. Free PVP monomers with lower concentration induced irregular particles, while the lower concentration of NaBH 4 led to the formation of small and regular nanosheets. Both particle size and morphology could be regulated with SDS concentration dependence if the SDS concentration was higher than the critical aggregation concentration. Higher SDS concentrations favoured smaller particle sizes and nanosheet formation. Two-dimensional planar Ag nanostructures were generated at pH 9-10, where [Ag(NH 3) 2 ] + existed at a stable complex ionisation state.

Surface plasmon resonance induced enhancement of photoluminescence and Raman line intensity in SnS quantum dot-Sn nanoparticle hybrid structure

“…There are reports that suggests that the addition of of NaBH 4 in high concentration could result in aggregation of nanoparticles. But in the presence of PVP whose role is to stabilize the particle growth and prevent aggregation, the increase in concentration of NaBH 4 results in different 2D structures [32]. The ratio of PVP and NaBH 4 plays a role is controlling the morphology, aspect ratio of the grown metal nanoparticles [33].…”

Rebuildable Silver Nanoparticles Employed as Seeds for Synthesis of Pure Silver Nanopillars with Hexagonal Cross-Sections under Room Temperature

“…Considering that the optimal carrier for silver nanoparticles is a natural polymer, this study employed sodium dodecyl sulfate as a surface stabilizer for synthesizing silver nanostructures, owing to its favorable interactions with polymers [ 47 , 48 , 49 , 50 , 51 ]. This method was used to obtain asymmetrical SNPs with hexagonal cross-sections at room temperature in high yield with high repeatability.…”