Achieving over 90% Faradaic Efficiency in Cyclohexanone Oxime Electrosynthesis Using the Cu-Mo Dual-Site Catalyst

Area of Science:

• Electrochemistry
• Materials Science
• Chemical Engineering

Background:

• Electrosynthesis of cyclohexanone oxime (CHO), a crucial nylon-6 precursor, offers a sustainable alternative to traditional methods.
• Current challenges include low efficiency due to difficulties in selectively producing the *NH2OH intermediate during nitrate electroreduction reaction (NitRR) at high current densities.

Purpose of the Study:

• To develop a high-performance electrocatalyst for efficient and selective *NH2OH production via NitRR.
• To enable high-yield electrosynthesis of cyclohexanone oxime (CHO) from cyclohexanone.

Main Methods:

• Fabrication of a Cu1MoO4/nitrogen-doped carbon (NC) electrocatalyst featuring high-density Cu-Mo dual sites.
• Electrochemical characterization and *NH2OH production via NitRR coupled with cyclohexanone oximation.
• In situ characterization to elucidate the catalytic mechanism.

Main Results:

• The Cu1MoO4/NC catalyst achieved a record CHO Faradaic efficiency of 94.5% and a yield rate of 3.0 mol g-1 h-1.
• High performance was maintained at an industrially relevant current density of 0.5 A cm-2.
• In situ studies confirmed that Cu-Mo dual sites selectively produce *NH2OH by inhibiting hydrodeoxygenation of intermediates.

Conclusions:

• The developed Cu1MoO4/NC electrocatalyst enables highly efficient and selective electrosynthesis of CHO.
• This catalyst demonstrates significant potential for industrial-scale production of CHO from nitrogenous waste.
• The findings offer a promising pathway for sustainable chemical manufacturing.