Enhanced Electrocatalytic C-N Coupling through Essential Electrochemical Potential Modulation of Cluster-Modified...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Urea is crucial for energy and agriculture, but its production via Haber-Bosch synthesis is energy-intensive and polluting.
• Electrocatalytic C-N coupling presents a sustainable alternative for urea synthesis.
• Efficient catalysts are essential for the viability of electrocatalytic C-N coupling.

Purpose of the Study:

• To identify and characterize an efficient electrocatalyst for urea synthesis.
• To investigate the mechanism of electrocatalytic C-N coupling under varying electrochemical potentials.
• To elucidate the electronic factors governing catalyst performance.

Main Methods:

• Computational screening of potential electrocatalysts.
• Density Functional Theory (DFT) calculations to study reaction mechanisms.
• Analysis of electronic structure and orbital hybridization.
• Investigation of electrochemical potential effects on catalytic activity.

Main Results:

• Cr4/Ti2CO2 identified as an optimal catalyst with a low overpotential (0.29 V) and kinetic barrier (0.40 eV).
• A novel 'Mixed Cooperative Orbital Hybridization Mechanism' was elucidated, explaining the role of d orbitals in N2 activation.
• Synergistic activation of the N≡N bond by specific d orbitals and d-band center was found crucial for C-N coupling.
• Optimal catalytic activity observed at 0.40 V vs. RHE in acidic conditions (pH 0).

Conclusions:

• Cr4/Ti2CO2 is a highly efficient electrocatalyst for urea synthesis.
• The study provides fundamental insights into potential-dependent electrocatalytic mechanisms.
• Findings guide the rational design of advanced electrocatalysts for sustainable chemical production.