The electrocatalyst with cost effective and high performance towards hydrazine electrooxidation is critical to promote the practical application of direct hydrazine fuel cell (DHFC). Herein, an effective approach is developed to study the Ni-Zn alloy as promising hydrazine electrocatalyst by the combined experimental and theoretical investigations. 3D nanosheet Ni-Zn alloy with single alpha-NiZn phase was successfully synthesized on Ni foam (NF) substrate through the electrodepostion of Ni-Zn alloy and followed electrochemical leaching. The Ni-Zn catalyst exhibits the synergetic capabilities of impressively high activity with a superior current density of 370 mA cm(-2) at 0.3 V, excellent durability with a retention rate of 88.7% after 5000 s and almost 100% selectivity for the complete electrooxidation of hydrazine, which is at the top level among the reported electrocatalysts for hydrazine oxidation up to now. The reason for the excellent durability of Ni-Zn catalyst was studied. Specially, first principles calculations were employed to shed light on the catalytic mechanism of high performance Ni-Zn catalyst. (C) 2019 Elsevier Ltd. All rights reserved.