Deformed One-Dimensional Covalent Organic Polymers for Enhanced CO Electroreduction to Methanol

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Polymeric frameworks with spatially arranged molecular catalysts improve catalytic performance by preventing aggregation.
• The influence of local coordination effects induced by polymerization on catalyst performance is not well understood.

Purpose of the Study:

• To develop one-dimensional cobalt-tetra-amino-phthalocyanine-based covalent organic polymers (1D-COP) for electrochemical CO reduction reaction (CORR).
• To investigate the impact of local curvature induced by carbon nanotube templates on 1D-COP catalytic activity.

Main Methods:

• Synthesis of 1D-COP using cobalt-tetra-amino-phthalocyanine.
• Templating 1D-COP onto single-walled carbon nanotubes (SWCNT) and multiwalled carbon nanotubes (MWCNT) of varying diameters.
• Electrochemical CO reduction reaction (CORR) testing in an H-cell.
• Characterization using X-ray and vibronic spectroscopies.
• Computational analysis using density functional theory (DFT).

Main Results:

• The 1D-COP/SWCNT catalyst achieved a maximum methanol Faradaic efficiency of 70%.
• Catalysts supported on wider MWCNTs showed significantly lower efficiencies (22% and 14%).
• Spectroscopic and DFT analyses revealed distinct local geometries and electronic structures due to COP-CNT interactions.
• Increased catalyst curvature correlated with enhanced *CO binding and improved reduction reactions.

Conclusions:

• Local coordination and curvature in polymeric frameworks are critical for optimizing electrocatalytic performance.
• The 1D-COP/SWCNT system demonstrates a promising strategy for efficient electrochemical CO reduction.
• This study underscores the importance of substrate-induced structural modifications in catalyst design.