Electroanalytical Assessment of Heavy Metals in Waters with Bismuth Nanoparticle-Porous Carbon Paste Electrodes

A Nanoscale paper on “Ultrafast continuous synthesis of crystalline ferrite nanoparticles in supercritical ethanol” (Oana Pascu, Samuel Marre, Cyril Aymonier and  Anna Roig) has recently been published. It is the result from the collaboration with the group of Cyril Aymonier from the ICMB-CNRS in Bordeaux, where Oana Pascu spent an internship during her Ph.D. and now she holds a post-doctoral contract.

Nanoscale 5 (2013) 2126-2132, DOI: 10.1039/c3nr33501a

Magnetic nanoparticles (NPs) are of increasing interest in various industrially relevant products. For these, the development of greener and faster approaches facilitating scaling-up production is of paramount importance. Here, we report a novel, green and potentially scalable approach for the continuous and ultrafast (90 s) synthesis of superparamagnetic ferrite NPs (MnFe₂O₄, Fe₃O₄) in supercritical ethanol (scEtOH) at a fairly moderate temperature (260 °C). ScEtOH exhibits numerous advantages such as its production from bio-resources, its lack of toxicity and its relatively low supercritical coordinates (p_c = 6.39 MPa and T_c = 243 °C), being therefore appropriate for the development of sustainable technologies. The present study is completed by the investigation of both in situ and ex situ NP surface functionalization. The as-obtainednanoparticles present good crystallinity, sizes below 8 nm, superparamagnetic behavior at room temperature and high saturation magnetization. Moreover, depending on the capping strategy, the ferrite NPs present extended (for in situ coated NPs) or short-term (for ex situ coated NPs) colloidal stability.