Flame spray synthesis of nano lanthanum strontium manganite for solid oxide fuel cell applications

Abstract

Lanthanum strontium manganite is a classic cathode material for solid oxide fuel cells (SOFC). Nanosized LSM particles, due to their higher specfic surface area, have been found to enhance the electrode performance by providing a larger three phase boundary (TPB) area. However conventional processes like solid state, sol-gel or co-precipitation, produce particles having low specic surface area (< 8 m 2 /g) and hence require high sintering temperatures. Moreover these processes are multi-step and are hence time consuming. In the present work, single phase LSM with a crystallite size of 26 nm and a specfic surface area as high as 40 m 2 /g was produced by a flame spray pyrolysis method. The as-synthesized powder was characterized by X-ray diffraction (XRD), nitrogen adsorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Porous thin films were prepared by spin coating a water based dispersion of LSM. Electrochemical performance of the nanoparticulate cathode films were studied using impedance spectroscopy. Interfacial polarization resistance value of as low as 0.085 :cm 2 at 850 o C was obtained by this method. This method thus offers a very cost effective approach for the preparation of highly active cathode thin films for SOFC applications.

Fluorescent magnetic nanoparticles for cell labeling: Flux synthesis of manganite particles and novel functionalization of silica shell

“…However, such treatment is accompanied by a broadening of the size distribution and the formation of a fraction of very fine fragments [21]. Several other synthetic procedures for LSMO nanoparticles have been reported, namely, the hydrothermal method [22,23], aerosol flame pyrolysis [24], and flux preparation, the so-called molten salt synthesis (MSS) [25,26], but only the last one seems to overcome the drawbacks of sol-gel routes with respect to the morphology and size distribution of the particles. However, LSMO nanoparticles prepared via MSS have not yet been tested in highly demanding applications such as those in biology or medicine, and existing reports address solely their magnetic properties and structure [27,28].…”