Cu[Ni(2,3-pyrazinedithiolate)₂] Metal-Organic Framework for Electrocatalytic Hydrogen Evolution.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Metal-organic frameworks (MOFs) are increasingly explored as electrocatalysts.
• Two-dimensional (2D) dithiolene-based MOFs show high activity for the hydrogen evolution reaction (HER).

Purpose of the Study:

• Evaluate a novel three-dimensional (3D) dithiolene-based MOF, Cu[Ni(2,3-pyrazinedithiolate)2] (1), as an electrocatalyst for HER.
• Investigate the catalytic performance and activation mechanism of MOF 1.

Main Methods:

• Electrochemical evaluation of MOF 1 in acidic aqueous electrolyte.
• Controlled potential electrolysis to study catalyst activation.
• Spectroscopic and computational analyses (density functional theory) to elucidate the activation mechanism.

Main Results:

• MOF 1 exhibits a catalytic onset at -0.43 V vs RHE and an overpotential of 0.53 V at 10 mA/cm2.
• An activation process significantly enhances catalytic activity, reducing onset potential and overpotential by 200 mV.
• Experimental and computational data support Cu-N bond cleavage as the activation mechanism.

Conclusions:

• The 3D dithiolene-based MOF, Cu[Ni(2,3-pyrazinedithiolate)2] (1), is a promising electrocatalyst for HER.
• Catalyst activation via Cu-N bond cleavage under reaction conditions leads to improved performance.
• This work highlights the potential of 3D MOFs for efficient small molecule activation.