Alkali Metal–Metal Exchange Reaction for Effective Synthesis of Functional Phosphate Salts

AMPO4 and MPO4 systems (A = alkali metal, M = metal) exhibit various optical and electrochemical functions. This study shows that such systems can be synthesized via an alkali metal–metal exchange reaction between A3PO4 and the metal salt of an acid with lower pKa than phosphoric acid. This method significantly improves the material designs and syntheses of various phosphate salts. Many kinds of functional phoshate salts are effectively synthesed via an alkali metal–metal exchange reaction between A3PO4 and the metal salt of an acid with lower pKa than phosphoric acid. The reaction mechanism is fundamental acid-base reaction between the salt of strong acid and weak base and the salts of weak acid and strong base.