A nanoporous gold (NP-Au) microelectrode is successfully prepared by applying potential cycling to a conventional microdisk electrode in nonaqueous electrolyte of ZnCl2 in benzyl alcohol at 120 C. During the cathodic process, Zn is electrodeposited and alloyed with the Au microdisk substrate to form AuZn alloy phase. During the anodic process, Zn is selectively dissolved from the alloy phase, leading to the formation of the NP-Au microelectrode. Continuous potential cycling enriches the nanostructures of the microelectrode. Scanning-electron microscope (SEM) and energy dispersive X-ray (EDX) microscope measurements show that the NP-Au microelectrode possesses nanoporous structures whose pore sizes are ranging from around 100 to 500 nm, and chemically contains a certain amount of Zn. The NP-Au microelectrode exhibits highly improved electrochemical responses compared to the polycrystalline Au microdisk electrode, largely due to its high surface area. The electrochemical oxygen reduction study provides an example for indicating that the NP-Au microelectrode is a promising technique for electrocatalysis and electroanalysis investigations. Therefore, the potential cycling tuned electrochemical alloying/dealloying will be an effective and convenient technique for the preparation of nanoporous microelectrodes with high surface areas. 2012 Elsevier B.V. All rights reserved.