Sol–gel derived La0.6Sr0.4CoO3 nanoparticles, nanotubes, nanowires and thin films

This work has demonstrated how to tailor the structure and form of the sol–gel derived La0.6Sr0.4CoO3 perovskite material from zero-dimension (nanoparticles) to one-dimension (nanotubes and nanowires) and two-dimension (thin films). The nanoparticles with a diameter of 50–100 nm are obtained by calcination of the pulverized gel powder. The nanotubes with a diameter of 100 nm and the nanowires with a diameter of 40–60 nm are formed by shaping the sol with the cylinder pores in an anodic aluminum oxide (AAO) template. The 150 nm thick thin film with the grain size of around 40 nm is prepared by spin coating the sol on a silicon substrate. The effects of the sol recipe on the formation of final product have been studied. A relatively high pH value of the sol and the addition of appropriate amount of chelating agent are critical to ensure the formation of the monolithic La0.6Sr0.4CoO3 perovskite structure. When preparing a thin film, ethylene glycol is an essential component for enhancing the affinity between the sol and the silicon substrate.