Electrosynthesis of Low Pt-Loaded High Entropy Catalysts for Effective Hydrogen Evolution with Improved Acidic Durability

초록

The synergistic effect in multi-metal electrocatalysts has gained attention as an efficient strategy for enhancing intrinsic electrocatalytic activities. In this study, a facile electrodeposition technique is used to synthesize a multi-metal high entropy catalyst (HEC) for efficient electrocatalytic hydrogen production. To boost the synergistic effect between noble metals and transition metals, the Pt ratio is controlled in a multi-metal electrocatalyst system. The prepared Pt-involved HEC (Pt-HEC) exhibits a bamboo-like morphology with uniformly distributed elements. The 2.5 mM Pt-HEC has outstanding electrocatalytic activity toward hydrogen evolution reaction (HER) among other Pt-HECs, with a low overpotential of 70 mV and a Tafel slope value of 47 mV dec(-1). Additionally, the Pt mass activity of the 2.5 mM Pt-HEC is 5.6 times higher than commercial Pt/C electrocatalyst owing to the improved synergistic effect with an optimized Pt ratio. According to the electrochemical impedance spectroscopy (EIS) analysis, the proton-coupled electron transfer (PCET) process occurs more quickly in the 2.5 mM Pt-HEC electrocatalyst, confirming its smaller charge transfer resistance properties compared to those of the 5 and 1 mM Pt-HEC. Therefore, HEC systems can be extensively encouraged as a platform for improving synergistic effects and enhancing electrocatalytic activities for a highly efficient HER electrocatalyst.

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