Carbide-Os Interactions Enhance Deuterium Evolution and Electrolytic Hydrogen Isotope Separation Efficiency

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Deuterium gas production via electrolysis relies on catalysts like Pt/C.
• Pt/C exhibits high cost, limited deuterium evolution reaction (DER) activity, and poor H/D separation.
• Developing cost-effective and efficient catalysts for DER is crucial.

Purpose of the Study:

• To investigate osmium (Os) catalysts supported on B4C and TiC for DER and H/D separation.
• To leverage strong metal-support interactions (SMSI) to tune catalyst performance.
• To provide mechanistic insights into SMSI-mediated DER kinetics.

Main Methods:

• Synthesis and characterization of Os/B4C and Os/TiC catalysts.
• Electrochemical evaluation of DER activity and H/D isotope separation.
• X-ray photoelectron spectroscopy (XPS) for electronic structure analysis.
• In situ attenuated total reflection-surface enhanced infrared absorption spectroscopy (ATR-SEIRAS).
• Density functional theory (DFT) calculations.

Main Results:

• Os/B4C demonstrated ultralow overpotentials for DER, outperforming Pt/C in activity and stability.
• Os/TiC achieved a high H/D isotope separation factor (6.0), superior to Pt/C (3.5).
• SMSI effects tuned Os electron density, influencing deuterium intermediate adsorption and reaction kinetics.
• B4C facilitated H2O and D2O dissociation, while TiC selectively promoted H2O dissociation.

Conclusions:

• Osmium-based catalysts supported on B4C and TiC offer a cost-effective and high-performance alternative to Pt/C for DER and H/D separation.
• SMSI is a viable strategy for optimizing catalyst performance through controlled electronic interactions.
• This work provides a practical approach for designing advanced catalysts for deuterium production and water isotope enrichment.