The development of efficient and robust electrocatalysts for the hydrogen evolution reaction (HER) is central to advancing sustainable hydrogen technologies. In this work, a palladium-modified stainless steel mesh (Pd/SSM) electrode was prepared and evaluated as a practical HER catalyst using a combination of structural, morphological, and electrochemical techniques.
X-ray diffraction (XRD) analysis confirms that the face-centered cubic structure of the stainless-steel mesh is preserved after Pd modification, demonstrating the structural stability of the support. Weak and broadened Pd-related diffraction features indicate the formation of nanocrystalline Pd domains. Scanning electron microscopy (SEM) reveals that Pd deposition induces a roughened surface morphology, with Pd-containing features distributed across the SSM surface, leading to increased surface area and enhanced accessibility of active sites. Transmission electron microscopy (TEM) further shows aggregated nanocrystalline Pd-containing domains. High-resolution TEM images display clear lattice fringes, while selected area electron diffraction patterns exhibit concentric rings, confirming the polycrystalline nature of the Pd phase.
Electrochemical evaluation demonstrates a substantial improvement in HER activity following Pd modification. The Pd/SSM electrode achieves an overpotential of 119 mV at a current density of 10 mA, significantly lower than that required for bare SSM (350 mV). This enhanced performance is attributed to the presence of crystalline Pd domains, increased surface roughness observed by SEM, and strong metal–support interaction, which collectively promote efficient charge transfer and hydrogen adsorption during HER.
Overall, the combined SEM, TEM, and electrochemical analyses highlight Pd/SSM as a structurally robust and effective HER electrode. This study demonstrates the potential of noble-metal-modified stainless steel substrates as scalable and practical catalysts for electrochemical hydrogen production.