Opportunity
Current electrocatalysts for hydrogen evolution reaction (HER) face significant limitations, particularly in achieving high efficiency and stability at industrial-scale current densities. Conventional metal/transition-metal dichalcogenide (TMD) hybrids often use mixed-phase TMD templates (e.g., 2H phase mixed with 1T or 1T' phase), which suffer from poor conductivity and phase boundaries that hinder electron transfer and catalytic performance. Additionally, existing methods struggle to achieve high-loading single-atom metal dispersion without nanoparticle formation, limiting their mass activity and practical applicability. The need for HER electrocatalysts that combine low overpotentials, high current densities (>1,000 mA cm⁻²), and long-term stability remains unmet.
Technology
This patent addresses these challenges by developing single-atomically dispersed metal (e.g., Pt, Au, Ni) hybrids on uniformly crystalline 1T'-phase TMD nanosheets (e.g., 1T'-MoS₂). The innovation lies in the high-purity 1T'-phase TMD templates, which enable epitaxial growth of single-atom metals (up to 10 wt% loading) without nanoparticle formation. Key steps include:
1. Electrochemical intercalation to exfoliate 1T'-TMD nanosheets with >90% phase purity.
2. Photoreduction or chemical reduction to deposit single-atom metals (e.g., Pt) on the TMD surface, forming stable Pt-S/Mo coordination.
The resulting hybrid (e.g., s-Pt/1T'-MoS₂) exhibits a thermoneutral hydrogen adsorption free energy (ΔG_H ≈ 0 eV), optimizing HER kinetics.
Advantages
- Ultralow overpotentials: 10 mV to reach 10 mA cm⁻², outperforming commercial Pt/C (19 mV).
- High current density: Achieves 1,500 mA cm⁻² at 112 mV, far below Pt/C (372 mV).
- Stability: Operates at 1,500 mA cm⁻² for 240 hours without degradation.
- Mass activity: 6.814 A mg⁻¹ at 40 mV, 2.66× higher than Pt/C.
- Tunable loading: Single-atom dispersion maintained up to 10 wt% metal loading.
Applications
- Hydrogen production: Water electrolysis for green energy.
- CO₂ reduction: Catalyzing CO₂-to-fuel conversions.
- Nitrogen fixation: Ambient-condition ammonia synthesis.
- Electrochemical devices: Fuel cells and batteries.
