Hydrothermal synthesis of potassium copper phosphate hydrate and ludjibaite microcrystals

A hydrothermal route has been designed for the selective synthesis of potassium copper phosphate hydrate [CuK(PO4)·H2O] (PCPH) and ludjibaite [Cu5(OH)4(PO4)2] microcrystals. The final products of this hydrothermal process are determined by the reaction media (in an ethanol/water mixed solvent). The ethanol molecule acts as a switch: when ethanol is added (volume ratio of ethanol to water being 3:1), the product is PCPH; when in the absence of ethanol, the product is ludjibaite. These results demonstrated that such a binary reaction media could provide an alternative and versatile strategy for controlling inorganic microcrystals by simply manipulating the supersaturation of the growing solution.