A green strategy for fabricating nanoparticles, creating nanoscale coatings and designing porous materials was reported in Nature Communications this week. The process exploits the superheated and charged environment within levitated Leidenfrost water droplets. It is a relatively low energy procedure and water is the only solvent required.

Everyone is familiar with the experience of sprinkling water onto a hot frying pan. The water drop vaporizes and appears to levitate upon its own vapour; this is the Leidenfrost effect in action. Mady Elbahri and colleagues have investigated these droplets and show them to be not only superheated, but also highly charged. They can thus be used as “microreactors” and their internal environments are ideal for nanosynthesis. The authors demonstrate this application by fabricating several nanoscale products such as nanoporous gold with wideband absorption, which can be coated onto a range of materials and may have energy harvesting applications.