Modulating Phase-Selective Dealloying and Structural Stability of a Self-Supporting Nanoporous CuZrAl MG Electrode via Trace Pd Decoration

Abstract

Combining high mechanical integrity with optimized catalytic kinetics remains a critical bottleneck for exploiting Cu-based nanoporous materials in the hydrogen evolution reaction (HER). In this work, a self-supporting nanoporous Cu-based metallic glass modified with trace Pd (np-Pd-CuZrAl) was fabricated via sequential phase-selective chemical dealloying and galvanic replacement. In 1.0 M KOH, the np-Pd-CuZrAl catalyst exhibits superior performance, requiring an overpotential of only 89.0 mV at 10 mA cm−2 with a low Tafel slope of 34.38 mV dec−1, maintaining exceptional activity after 100 h of continuous operation. Notably, nanoindentation and tensile testing demonstrate the exceptional deformation tolerance of the np-Pd-CuZrAl electrode, which successfully retains its structural and electrochemical functionality under severe tensile and bending deformations. In situ Raman spectroscopy and DFT calculations demonstrate that Pd incorporation effectively tunes the d-band center, enhances interfacial water adsorption, and inhibits surface oxidation. Furthermore, a water-splitting cell using this cathode achieves 10 mA cm−2 at 1.54 V. This work establishes a compelling strategy to modulate atomic configuration and mechanical stability in freestanding metallic glass electrodes, providing deep metallurgical insights.