A simple setup miniaturization with multiple benefits for Green Chemistry in nanoparticle synthesis

Abstract

The development of nanomaterials often relies on wet-chemical syntheses performed in reflux-setups using round-bottom-flasks. An alternative approach to synthesize nanomaterials is here presented that uses glass tubes designed for NMR analysis as reactors. This approach uses less solvent, uses less energy, generates less waste, provides safer conditions, is less prone to contamination and is compatible with high throughput screening. The benefits of this approach are illustrated by an in breadth study with the synthesis of gold, iridium, osmium and copper sulfide nanoparticles.

Surfactant-Free Colloidal Syntheses of Precious Metal Nanoparticles for Improved Catalysts

“…258 Pt has been the most studied material, and size controlled was achieved using alcohol/water mixtures. To date, size control remains more challenging for Ir NPs 259,260 or Os NPs, 260,261 as summarized in Table 2. In the case of Ir and Os NPs, the reaction can proceed without base to obtain NPs, 261,262 but the activity and probably the yield of the synthesis are improved using alkaline conditions.…”

“…264,265 One drawback of the synthesis is it requires a relatively low concentration of precursor in the case of Pt (2.5 mM) 25 but was shown to lead to small size Ir NPs even at a high precursor concentration of 100 mM. 260,266 The related Ir NPs were shown to be up to 10× more active than the state-of-the-art for the OER. 25,265 It is expected that the high activity of the catalyst obtained will help to discriminate in more depth NP size or support effects as well as the importance of selecting the right solvent to obtain optimal catalysts.…”