Volatilized Molten Salts: An Alternative Avenue for Synthesizing Single-Phase Perovskites

Single-phase La_0.8Sr_0.2MnO₃ (LSM) has been synthesized using a volatilized molten salt synthesis (vMSS) method for the first time with a LiCl-KCl eutectic with diameters of up to 300 nm, with the majority ranging from 50 to 100 nm. While deleterious to LSM formation when the MSS takes place in the liquid phase, a LiCl-KCl eutectic successfully facilitates LSM formation when volatilized. Specifically, KCl evaporates more readily than LiCl and promotes the formation of LSM via the vapor phase. As time progresses, LiCl volatilization increases and contributes negatively to Sr stoichiometry in the perovskite phase in accordance with Lux-Flood chemistry and to product phase purity. The vMSS is therefore a way to obviate the more immediate restrictions of Lux-Flood chemistry in the liquid phase. These results demonstrate the surprising versatility and flexibility of the MSS method to synthesize numerous potential energy-relevant materials with greater ease than previously thought.