Two-dimensional mineral hydrogel-derived single atoms-anchored heterostructures for ultrastable hydrogen evolution

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Hydrogen energy is crucial for carbon neutrality.
• Single atom-anchored heterostructured catalysts are ideal for hydrogen production.
• Large-scale, stable, and cost-effective fabrication of these catalysts remains challenging.

Purpose of the Study:

• To develop a scalable method for producing single atom-anchored heterostructured catalysts.
• To investigate the hydrogen evolution reaction (HER) activity and stability of these catalysts.
• To understand the mechanism behind their catalytic performance.

Main Methods:

• Synthesis of single iron (Fe) atom-dispersed heterostructured Mo-based nanosheets from a mineral hydrogel.
• Electrochemical testing for HER activity and long-term stability in alkaline conditions.
• Density functional theory (DFT) calculations to elucidate the catalytic mechanism.

Main Results:

• The synthesized nanosheets demonstrated excellent HER activity with an overpotential of 38.5 mV at 10 mA cm⁻².
• Exceptional stability was observed, with no performance degradation over 600 hours at current densities up to 200 mA cm⁻².
• DFT results indicated that O-coordinated single Fe atoms facilitated H₂O adsorption and H* adsorption/desorption.

Conclusions:

• A green and scalable method for producing single-atom-dispersed heterostructured HER electrocatalysts was established.
• These catalysts exhibit superior performance and stability compared to many non-noble metal alternatives.
• The findings hold significant implications for the large-scale implementation of hydrogen energy.