Batch synthesis of rare-earth nickelates electronic phase transition perovskites via rare-earth processing intermediates

The rare-earth nickelates (RENiO3) exhibit an exceptional complex electronic phase diagram and multiple electronic phase transitions that enrich promising applications in correlated electronic devices beyond conventional semiconductors. Nevertheless, the practical applications of RENiO3 are challenged by their intrinsic thermodynamic metastability in material synthesis and high material cost. Therefore, developing an economical strategy to achieve the batch synthesis of RENiO3 is of vital importance. In this work, we enlarged the synthesis amount of RENiO3 up to 20 g per batch using chloride (KCl) assisted molten salt reaction. By optimizing the reaction conditions, the powder of RENiO3 with the cubic shape and average size of similar to 2 mu m was effectively synthesized, while their phase purity exceeded 95%. In addition, the cost to synthesize RENiO3 was further reduced by using rare-earth extraction intermediate products as the raw materials, instead of using the pure rare-earth precursors. It also achieved wide adjustments in the metal-to-insulator-transition temperature from 160 to 420 K without significantly reducing the transition sharpness. By enlarging the synthesis amount and the reducing the cost, it paves the way to the device application of RENiO3.