Novel synthesis and magnetocaloric assessment of functional oxide perovskites

The magnetic entropy change associated with the ferromagnetic Curie transition has been studied in La0.85Sr0.15MnO3 (LSM) perovskites obtained by both the citrate–nitrate gel autoignition and combustion thermal spray techniques. A modest magnetic entropy change can be observed in La0.85Sr0.15MnO3 by sintering the precursor-derived powder at 1200 °C for 16 h or by combustion spraying the solution precursor onto an Al substrate and annealing at 800 °C for 6 h. The combustion thermal spray process with rapid deposition rates and relatively low deposition temperature directly produces a microcrystalline perovskite phase. This microcrystalline powder can be processed more rapidly and at lower temperatures than that derived from the sol–gel syntheses process to produce material with fine crystallinity and an obvious magnetocaloric effect.