Cobalt Schiff-base complexes for electrocatalytic hydrogen generation

Area of Science:

• Inorganic Chemistry
• Electrochemistry
• Catalysis

Background:

• Proton reduction is a key reaction in sustainable energy technologies, such as water splitting.
• Developing efficient and inexpensive electrocatalysts for proton reduction is crucial for advancing these technologies.
• Cobalt complexes with Schiff-base ligands are explored as potential alternatives to precious metal catalysts.

Purpose of the Study:

• To synthesize and characterize two novel cobalt(III) complexes with Schiff-base ligands.
• To evaluate the electrocatalytic activity of these complexes for proton reduction.
• To investigate the kinetic properties and efficiency of the developed catalysts.

Main Methods:

• Synthesis and characterization of cobalt(III) Schiff-base complexes.
• Electrochemical measurements including cyclic voltammetry and foot-of-the-wave analysis.
• Analysis of catalytic Tafel plots to determine kinetic parameters.

Main Results:

• Both dinitro and tetranitro cobalt(III) Schiff-base complexes demonstrated activity for proton reduction.
• Catalytic activity was observed at low overpotentials of 120 mV and 280 mV, respectively.
• Foot-of-the-wave analysis indicated a theoretical maximum turnover frequency (TOFmax) up to 4100 s⁻¹, with experimental TOFs of 7 s⁻¹ and 3 s⁻¹.

Conclusions:

• The studied cobalt(III) Schiff-base complexes are effective electrocatalysts for proton reduction.
• These complexes offer a promising, low-cost alternative to traditional precious metal catalysts.
• Further optimization could lead to highly efficient catalysts for electrochemical energy conversion.