Hydrogen evolution reaction mediated by an all-sulfur trinuclear nickel complex

Area of Science:

• Inorganic Chemistry
• Electrochemistry
• Catalysis

Background:

• Nickel complexes are crucial in catalysis.
• Hydrogen evolution is a key area in renewable energy research.
• Understanding coordination spheres is vital for catalyst design.

Purpose of the Study:

• To synthesize and characterize a novel trinuclear nickel complex.
• To investigate its electrocatalytic activity for hydrogen evolution.
• To elucidate the mechanism of catalysis using computational studies.

Main Methods:

• Trinuclear nickel complex synthesis.
• X-ray diffraction for solid-state structure determination.
• Nuclear Magnetic Resonance (NMR) and UV-Vis spectroscopy for solution characterization.
• Electrocatalysis experiments for hydrogen evolution.
• Density Functional Theory (DFT) calculations.

Main Results:

• Successful synthesis and characterization of a trinuclear nickel complex.
• Square planar geometries and an all-sulfur coordination sphere confirmed.
• Significant electrocatalytic activity for hydrogen evolution observed in N,N-Dimethylformamide (DMF).
• DFT studies indicated a proton relay mechanism involving sulfur atoms.

Conclusions:

• The novel trinuclear nickel complex is a promising electrocatalyst for hydrogen evolution.
• The all-sulfur coordination sphere and square planar geometry are key features for activity.
• The proposed sulfur-mediated proton relay mechanism offers insights into hydrogenase function.