Highly reproducible, high-yield flow synthesis of gold nanoparticles based on a rational reactor design exploiting the reduction of passivated Au(iii)

Abstract

A highly-reproducible, high-yield flow synthesis of gold nanoparticles is developed based on synthesis kinetics from a high-pH gold precursor solution.

A study of the interaction of cationic dyes with gold nanostructures

“…Au seeds. 9,25,26 The LSPR band is observed around 535 nm. Compared to 50 nm citrate-capped AuNPs (Fig.…”

“…25 nm citrate-capped AuNPs were produced in batch with a seeded-growth approach, starting from the 11 nm citrate-capped AuNPs. These were grown using an extension of the passivated method from Panariello et al, 10 with Au(OH) 4 À as the precursor and citric acid as the reducing agent. 20 and 50 nm citrate-capped AuNPs were produced using an iterative seeded growth approach with hydroxylamine as the reducing agent, following the method reported by Brown et al 15 and using the 11 nm citrate-capped AuNPs as seeds.…”

“…27 For Tris-capped AuNPs, the chelating Tris-base ligand is expected to be more tightly attracted to the AuNPs, as it is a tridentate ligand. 9 On the other hand, the citrate ligand is not as strong and the binding mode of citrate in the stabilization of AuNPs highly depends on the citrate : Au ratio, which is much more readily affected by the environment. 28 Thus, although N-Au interactions are relatively weak, having three per molecule is likely to offer better adherence and protection against an incoming dye than the citrate-capped NPs.…”

“…Here we build on earlier work, 7,8 investigating how interactions between dyes and AuNCs and AuNPs of various size and surface chemistry enhance UV-visible absorption, investigating how the dye-gold interaction is affected by changes in these parameters. To this aim, we synthesized AuNCs and NPs according to various protocols, [9][10][11] enabling control of particle features such as size and surface chemistry.…”

Synthetic guidelines for the precision engineering of gold nanoparticles

“…At the same time, the study of the synthesis kinetics could render the translation of batch protocols to flow an easier task [39]. This was recently demonstrated by Panariello et al who translated an Au nanoparticle synthesis to flow with minimal effort [50]. Batch studies provided the relevant kinetic information on precursor conversion, which enabled the design of a flow reactor with throughput 20 mL/h (~1 mgAu/h) and a production volume limited only by the syringes used.…”