Synthesis of single-crystal perovskite PbCrO3 through a new reaction route at high pressure

As a new member in the family of Mott system, perovskite PbCrO₃ has recently been uncovered to exhibit fantastic structural transition under pressure, coupled with magnetic, electronic, and ferromagnetic transitions, which provide many opportunities for understanding of correlated system. However, it is still challenging to synthesize high-quality single-crystal PbCrO₃, leading to the limited exploration of this Mott compound. In this work, we formulate a new high-pressure reaction route for preparation of high-quality PbCrO₃ crystals between PbCl₂ and Na₂CrO₄ at high pressure of 5–10?GPa and at high temperature of 750–1500°C. Because of the formation of reaction byproduct NaCl, the final product can readily be separated by washing with water. The obtained sample is in the form of single crystal with crystallite size up to 200?μm. In addition, combined with X-ray diffraction measurement, a tentative pressure-temperature synthesis diagram of PbCrO₃ is mapped out from the reaction between PbCl₂ and Na₂CrO₄ and the reaction mechanism is also explored in detail.