Editing Phenoxazine-Sensitized CO2-to-CO Reduction with an Iron Porphyrin Catalyst: A Redox Properties-Catalytic Performance Study

{{DOI|doi=10.1002/cptc.202200009}}
[[Category:Photocatalytic CO2 conversion to CO]]
{{BaseTemplate}}

===Abstract===
====Summary====
A photochemical reduction of CO<sub>2</sub> to CO was shown using the iron porphyrin complex {{#moleculelink:|link=FAKQJSUSUXMEFI-NGWNFTKISA-M|image=false|width=300|height=200}} as catalyst, screening the effect of different phenoxazine-based photosensitizers on the CO production. Turnover numbers (TONs) of 115 and a selectivity of 100% for CO were reached in acetonitrile in combination with the photosensitizer {{#moleculelink:|link=HDOFYEULLIFSQY-UHFFFAOYSA-N|image=false|width=300|height=200}}. The experiments were conducted under visible-light irradiation (λ > 400 nm) using BIH as sacrificial electron donor (see section SEDs below).
====Advances and special progress====
In this study, the authors showed a strong relation between the oxidation potential of the photosensitizer and the CO production whereas no correlation between the CO production and the excited state potential of the photosensitizer was discovered. This identifies the electron transfer to regenerate the photosensitizer as a determining step and demonstrates the importance of improving the interaction between the photosensitizer and the sacrificial electron donor for optimization of the CO<sub>2</sub> reduction. 
====Additional remarks====
The tested phenoxazine-based photosensitizers performed similarly in combination with the iron porphyrin complex and allowed for TONs of 88-115 and selectivities of 80-100% apart from complex {{#moleculelink:|link=JUDLWUDCWSBXOA-UHFFFAOYSA-N|image=false|width=300|height=200}} that showed both a lower TON (32) and decreased selectivity (36%).

===Content of the published article in detail ===
The article contains results for the reduction of CO<sub>2</sub> to CO under visible-light catalysis using an iron complex and different phenoxazine-based photosensitizers. The catalytic system performs best (referring to the TON of CO production) in acetonitrile.
====Catalyst====
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</chemform>

====Photosensitizer====
{{#moleculelink:|link=IGGSSEOAGCUGDJ-UHFFFAOYSA-N|image=true}} {{#moleculelink:|link=WKYXCCICHXAEHL-UHFFFAOYSA-N|image=true}}{{#moleculelink:|link=HDOFYEULLIFSQY-UHFFFAOYSA-N|image=true}}{{#moleculelink:|link=ZIGQSGYNHLDFOD-UHFFFAOYSA-N|image=true}}{{#moleculelink:|link=JUDLWUDCWSBXOA-UHFFFAOYSA-N|image=true}}{{#moleculelink:|link=JLXPQUVLGFUEHE-UHFFFAOYSA-N|image=true}}

====Investigation====
{{#experimentlist:|form=Photocatalytic_CO2_conversion_experiments|name=Table 1}}
====Sacrificial Electron Donor ====
In this study, the experiments were done with the sacrificial electron donor BIH ({{#moleculelink:|link=VDFIVJSRRJXMAU-UHFFFAOYSA-N|image=false|width=300|height=200}}).
==== Additives====
In this study, {{#moleculelink:|link=RHQDFWAXVIIEBN-UHFFFAOYSA-N|image=false|width=300|height=200}} was used as an additive.
Description	What you type	What you get
Italic	''Italic text''	Italic text
Bold	'''Bold text'''	Bold text
Bold & italic	'''''Bold & italic text'''''	*Bold & italic text*