Room-Temperature Synthesis of Intermetallic Cu-Zn by an Electrochemically Induced Phase Transformation

Ordered intermetallic compounds (OICs) are useful materials for applications ranging from catalysis to optoelectronics. However, generalizable synthetic methods for preparing OIC nanomaterials composed of an electropositive metal and late transition metal has remained a substantial challenge. Herein, we report a process for synthesizing ordered intermetallic gamma-Cu5Zn8 or intermetallic beta-CuZn (high-temperature phase) from Zn-rich Cu alloys at room temperature and atmospheric pressure by an electrochemically induced phase transformation (EIPT). In the EIPT process, Zn is dissolved from the lattice by electrochemical corrosion, initiating the reorganization of the crystal to an intermetallic phase. The transformation of epsilon-CuZn4 (space group: P6(3)/mmc) to ordered intermetallic gamma-Cu5Zn8 (space group: I (4) over bar 3m) or intermetallic beta-CuZn (space group: I (4) over bar 3m) is controlled by the potential and electrolyte used during dealloying. The phases that were accessed was gated by the thermodynamic stability of Zn-rich Cu alloys in aqueous electrolytes. These results have established a key development in the synthesis of intermetallic nanomaterials at room temperature and atmospheric pressure.

Automated summary

This study reports a new method for synthesizing ordered intermetallic compounds from zinc-rich copper alloys at room temperature and atmospheric pressure using an electrochemically induced phase transformation process.