# Support‐Induced Interfacial Effects Steer Methanol Selectivity in CO2 Electroreduction by Immobilized Cobalt Phthalocyanine

## TL;DR

Putting cobalt phthalocyanine on a carbon support changes its CO2 reduction product from CO to methanol, as revealed by simulations showing how the support affects the reaction environment.

## Contribution

The study reveals that the carbon support actively modulates the catalytic environment through desolvation, enabling selective methanol production.

## Key findings

- Immobilizing CoPc on carbon nanotubes shifts CO2 reduction selectivity from CO to methanol.
- Support-induced desolvation lowers the protonation barrier for methanol production without affecting CO desorption.
- Interfacial electric fields and cations further enhance the selectivity for methanol.

## Abstract

Achieving product selectivity in multistep electrocatalysis requires delicately tuning the stability of key reaction intermediates to modulate the energetics of competing pathways. The conversion of CO2 by cobalt phthalocyanine (CoPc) presents a stark puzzle in this context; while solution‐phase CoPc exclusively produces CO, its immobilization on carbon nanotube support triggers a substantial and unusual switch to methanol. Here, using multiscale simulations, we resolve this outstanding puzzle. We demonstrate that the carbon support is not a passive anchor but an active modulator of the catalytic environment. It functions by shielding one face of the CoPc molecule from the aqueous solvent, which substantially lowers the kinetic barrier for protonation while having little effect on CO desorption, thereby activating methanol production. Interfacial electric fields (EF) and cations further enhance this effect. Our findings establish support‐induced desolvation as a new, rational design guideline for kinetically steering complex electrocatalytic reactions, providing a clear mechanistic basis for the unique reactivity of heterogenized molecular catalysts.

Immobilizing CoPc on a carbon support switches its CO2 reduction selectivity from CO to CH3OH. Multiscale simulations reveal that the support actively modulates the catalytic environment by inducing desolvation of bottom layer of CoPc, which lowers the protonation barrier while leaving CO desorption nearly unaffected.