Atom‐Efficient Ir Nanoclusters in Laser‐Engineered MoC@N‐Carbon for Ultralow‐Overpotential Hydrogen Evolution

Why It Matters

The breakthrough offers a cost‑effective, high‑performance alternative to platinum, accelerating low‑energy hydrogen production and hydrazine‑based energy storage at industrial scales.

Key Takeaways

• Laser‑engineered Ir nanoclusters achieve 25 mV HER overpotential.
• Catalyst outperforms Pt/C in both HER and hydrazine oxidation.
• Interfacial electronic polarization drives superior activity, not covalent bonds.
• Enables 0.08 V cell voltage for 10 mA cm⁻² hydrazine splitting.
• Maintains 100‑hour durability with ~95% hydrazine utilization.

Pulse Analysis

The synthesis route combines self‑polymerization with pulsed laser irradiation in liquids, a technique that simultaneously crystallizes MoC and enriches pyridinic‑N defects. This dual‑defect strategy produces a highly polarized Mo–Ir–N interface, facilitating rapid charge transfer without relying on traditional covalent bonding. Such interfacial engineering is gaining traction as a scalable pathway to maximize the intrinsic activity of scarce noble metals while minimizing their loading.

Electrochemical testing in alkaline media shows the IrNC/MoC@NC catalyst achieving 25 mV overpotential at 10 mA cm⁻² for HER, markedly lower than the 43 mV required by Pt/C. For the hydrazine oxidation reaction, the catalyst reaches 338 mV with a mass activity of 133.6 A g⁻¹, placing it among the most active reported systems. The combined HER/HZOR performance enables a symmetric electrolyzer to split hydrazine at cell voltages of 0.08 V (10 mA cm⁻²) and 0.31 V (50 mA cm⁻²), delivering near‑complete reagent utilization and stable operation over 100 hours.

Beyond laboratory metrics, the technology addresses two critical bottlenecks for clean energy: reducing reliance on platinum‑group metals and lowering the energy input for hydrogen generation. The laser‑engineered approach is compatible with roll‑to‑roll processing, suggesting a viable route to commercial‑scale production. As industries explore hydrazine as a high‑energy‑density carrier, catalysts like IrNC/MoC@NC could underpin next‑generation electrolyzers that deliver both economic and environmental benefits.