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Abstract Development of high‐performance, low‐cost catalysts for electrochemical water splitting is key to sustainable hydrogen production. Herein, ultrafast synthesis of carbon‐supported ruthenium–copper (RuCu/C) nanocomposites is reported by magnetic induction heating, where the rapid Joule's heating of RuCl3and CuCl2at 200 A for 10 s produces Ru–Cl residues‐decorated Ru nanocrystals dispersed on a CuClxscaffold, featuring effective Ru to Cu charge transfer. Among the series, the RuCu/C‐3 sample exhibits the best activity in 1 mKOH toward both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), with an overpotential of only −23 and +270 mV to reach 10 mA cm−2, respectively. When RuCu/C‐3 is used as bifunctional catalysts for electrochemical water splitting, a low cell voltage of 1.53 V is needed to produce 10 mA cm−2, markedly better than that with a mixture of commercial Pt/C+RuO2(1.59 V). In situ X‐ray absorption spectroscopy measurements show that the bifunctional activity is due to reduction of the Ru–Cl residues at low electrode potentials that enriches metallic Ru and oxidation at high electrode potentials that facilitates the formation of amorphous RuOx. These findings highlight the unique potential of MIH in the ultrafast synthesis of high‐performance catalysts for electrochemical water splitting.
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This content will become publicly available on May 15, 2026
Carbon Monoxide-Assisted Synthesis of Nickel Cobalt Phosphide Nanorods for the Hydrogen Evolution Reaction
The development of efficient and cost-effective catalysts for hydrogen evolution reaction (HER) is crucial for the advancement of electrochemical water splitting technology. Here, we report a novel synthetic method for the preparation of single-crystalline NiCoP nanorods with tunable aspect ratios using a CO-assisted, trioctylphosphine (TOP)-mediated approach. The introduction of CO gas at different temperatures allows for the control of the nanorod growth, resulting in various aspect ratios while maintaining a hexagonal crystal structure and a composition of 1:1 Ni/Co as NiCoP. Our results demonstrate that the NiCoP nanorods with higher aspect ratios exhibit improved HER activity and stability, with the highest aspect ratio nanorods showing the lowest overpotential and Tafel slope in both acidic and alkaline media. This study highlights the importance of controlling the size and morphology of bimetallic phosphide nanoparticles to optimize their catalytic activity for HER, providing new insights into the design and optimization of nanostructured catalysts for electrochemical water splitting applications.
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- Award ID(s):
- 2304999
- PAR ID:
- 10625126
- Publisher / Repository:
- Scilight
- Date Published:
- Journal Name:
- Materials and Interfaces
- ISSN:
- 2982-2394
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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