Instantaneous and Continuous Mild Synthesis of PtPdCo/CeO 2 by High-Gravity Technology toward Efficient Hydrogen Evolution Reaction

Platinum (Pt)-based alloys have become common optimization methods for hydrogen evolution reaction (HER) catalysts in recent years by a positive lattice distortion effect and lower noble-metal usage. However, existing synthesis methods are usually complex for achieving alloying. Herein, a high-performance PtPdCo/CeO 2 catalyst with an ultrasmall particle size of 2.8 nm is instantaneously and continuously synthesized in an aqueous phase at room temperature by utilizing a high-gravity rotating packed bed reactor. For HER in alkaline medium, the as-prepared catalyst exhibits an overpotential of 18 mV at 10 mA·cm –2 and possesses a mass activity of 2.68 A·mg Pt –1, which is 2.0 times and 7.7 times higher than those of the conventional beaker product and commercial Pt/C. In addition, PtPdCo/CeO 2 as the ternary alloy catalyst exhibits better HER catalytic performance with the highest mass activity, 5.6 times and 3.2 times higher than PtCo/CeO 2 and PtPd/CeO 2, respectively. The incorporation of low-content Pd has a significant effect on the structure and electronic state of PtCo, with a great performance improvement. This work provides a convenient and continuous strategy to stably synthesize supported Pt-based catalysts with enhanced catalytic performance.