3D hierarchically porous Cu@Cu2O films supported Pd nanoparticles with excellent electrocatalytic activity are synthesized through electrochemical deposition, anodic oxidation and redox growth. Enzyme-free glucose biosensors based on the porous Cu@Cu2O-Pd electrodes exhibit higher sensitivity (1.157 mA cm (2)mM (1)) than those of the porous Cu@Cu2O films (0.607 mA cm (2)mM (1)), porous Cu films (0.507 mA cm (2)mM (1)) and Pd nanoparticles (0.107 mA cm (2)mM (1)). The enhanced activity of the porous Cu@Cu2O-Pd nanostructures might be attributed to the unique hierarchical porous structures with highly exposed active sites and synergetic effect from metal oxide semiconductor Cu2O and noble metal Pd. (C) 2017 Elsevier Ltd. All rights reserved.