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  • Aqueous Photoelectrochemical CO 2 Reduction to CO and Methanol over a Silicon Photocathode Functionalized with a Cobalt Phthalocyanine Molecular Catalyst
Title: Aqueous Photoelectrochemical CO 2 Reduction to CO and Methanol over a Silicon Photocathode Functionalized with a Cobalt Phthalocyanine Molecular Catalyst
Abstract We report a precious‐metal‐free molecular catalyst‐based photocathode that is active for aqueous CO 2 reduction to CO and methanol. The photoelectrode is composed of cobalt phthalocyanine molecules anchored on graphene oxide which is integrated via a (3‐aminopropyl)triethoxysilane linker to p‐type silicon protected by a thin film of titanium dioxide. The photocathode reduces CO 2 to CO with high selectivity at potentials as mild as 0 V versus the reversible hydrogen electrode (vs RHE). Methanol production is observed at an onset potential of −0.36 V vs RHE, and reaches a peak turnover frequency of 0.18 s −1 . To date, this is the only molecular catalyst‐based photoelectrode that is active for the six‐electron reduction of CO 2 to methanol. This work puts forth a strategy for interfacing molecular catalysts to p‐type semiconductors and demonstrates state‐of‐the‐art performance for photoelectrochemical CO 2 reduction to CO and methanol.  more » « less
Award ID(s):
2129963
PAR ID:
10463191
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
4
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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