Exchange Coupling Determines Metal-Dependent Efficiency for Iron- and Cobalt-Catalyzed Photochemical CO2 Reduction: Difference between revisions

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[[Category:Publication]]
[[Category:Publication]]
====Summary ====
====Summary ====
A {{Annotation|property=Tag|value=photocatalytic CO2 reduction; voc4cat; voc4cat:0000099|display=photochemical reduction of CO2}} to {{Annotation|property=Tag|value=CO;;|display=CO}} was shown using an Fe2+ and Co2+ complexes as catalysts in combination with Ruxx as photosensitizer.  
A {{Annotation|property=Tag|value=photocatalytic CO2 reduction; voc4cat; voc4cat:0000099|display=photochemical reduction of CO2}} to {{Annotation|property=Tag|value=CO;;|display=CO}} was shown using an Fe2+ and Co2+ complex as catalysts in combination with different photosensitizers. The authors examined the efficiency for photocatalytic CO2RR pending on metal−ligand exchange coupling as an example of charge delocalization. The iron complex {{#moleculelink:|link=YJOFQAAXFUIRKO-UHFFFAOYSA-N|image=false|width=300|height=200}} and cobalt complexes{{#moleculelink:|link=GEWRDVXFGQMHJL-UHFFFAOYSA-N|image=false|width=300|height=200}}, both bearing the redox-active ligand tpyPY2Me  were tested in comparison. It was found that the two-electron reduction of the Co(tpyPY2Me)]2+ catalyst {{#moleculelink:|link=GEWRDVXFGQMHJL-UHFFFAOYSA-N|image=false|width=300|height=200}} occurs at potentials 770 mV more negative than the Fe(tpyPY2Me)]2+ analogue{{#moleculelink:|link=YJOFQAAXFUIRKO-UHFFFAOYSA-N|image=false|width=300|height=200}} due to maximizing the exchange coupling in the latter compound.  
====Advances and special progress====


metal−ligand exchange coupling as an example of charge delocalization that can determine the efficiency for photocatalytic CO2RR. A comparative evaluation of iron and cobalt complexes supported by the redox-active ligand tpyPY2Me establishes that the two-electron reduction of [Co(tpyPY2Me)]2+ ([Co]2+) occurs at potentials 770 mV more negative than the [Fe(tpyPY2Me)]2+ ([Fe]2+) analogue by maximizing the exchange coupling in the latter compound.
====Advances and special progress====
====Additional remarks====
====Additional remarks====


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=== Investigation ===
=== Investigation ===
{{#experimentlist:|form=Photocatalytic_CO2_conversion_experiments|name=Iron-Catalyzed Photochemical CO2 Reduction under diverse conditions|importFile=Exchange Coupling Determines Metal-Dependent Efficiency for Iron- and Cobalt-Catalyzed Photochemical CO2 Reduction.xlsx}}


===Further Information===
 
The Supporting Information gives quantum yields for described experiments in Table 1.
General details for the experimental setup: Conducted inside a 25 mL borosilicate culture tube with a stir bar, a rubber septum, and an aluminum crimped top. The reaction vessel contained 5 mL of CH3CN, 2 μM of the catalyst, 200 μM of the photosensitizer, 100 mM BIH (112 mg), and 1 M phenol (470 mg). The reaction tubes were sparged with CO2 for 10 min, followed by injection of a gaseous internal standard (0.1 mL of C2H6). The reactions were placed on a stirplate 13 cm from two Kessil blue LED lamps (440 nm) for 15 or 30 min at a time and maintained at ambient temperature using a fan. Analysis of the headspace by Gas Chromatography (GC).{{#experimentlist:|form=Photocatalytic_CO2_conversion_experiments|name=CO2 Reduction under diverse conditions with diverse sensitizers|importFile=Exchange Coupling Determines Metal-Dependent Efficiency for Iron- and Cobalt-Catalyzed Photochemical CO2 Reduction_2.xlsx}}
 
The values in Table 2 include TOF numbers given in TON/min
 
{{#experimentlist:|form=Photocatalytic_CO2_conversion_experiments|name=Results Co2+ experiments taken from SI|importFile=Exchange publication_table 2.xlsx}}
 
=== Further Information ===
The results for the catalytic activity of the Co2+ compound {{#moleculelink:|link=GEWRDVXFGQMHJL-UHFFFAOYSA-N|image=false|width=300|height=200}} in Table 2 were gained from the Supporting Information.  
====Sacrificial electron donor====
====Sacrificial electron donor====
In this study, the experiments were done with the sacrificial electron donor BIH ([[Molecule:100508|100508]]).
In this study, the experiments were done with the sacrificial electron donor BIH ([[Molecule:100508|100508]]).
====Additives====
====Additives====
Different sources of protons were used, e.g. {{#moleculelink:|link=ISWSIDIOOBJBQZ-UHFFFAOYSA-N|image=false|width=300|height=200}}, {{#moleculelink:|link=RHQDFWAXVIIEBN-UHFFFAOYSA-N|image=false|width=300|height=200}} and {{#moleculelink:|link=WXNZTHHGJRFXKQ-UHFFFAOYSA-N|image=false|width=300|height=200}}

Latest revision as of 23:34, 22 November 2024


Abstract[edit | edit source]

Summary[edit | edit source]

A photochemical reduction of CO2 to CO was shown using an Fe2+ and Co2+ complex as catalysts in combination with different photosensitizers. The authors examined the efficiency for photocatalytic CO2RR pending on metal−ligand exchange coupling as an example of charge delocalization. The iron complex 100968 and cobalt complexes100969, both bearing the redox-active ligand tpyPY2Me were tested in comparison. It was found that the two-electron reduction of the Co(tpyPY2Me)]2+ catalyst 100969 occurs at potentials 770 mV more negative than the Fe(tpyPY2Me)]2+ analogue100968 due to maximizing the exchange coupling in the latter compound.

Advances and special progress[edit | edit source]

Additional remarks[edit | edit source]

Content of the published article in detail[edit | edit source]

Catalysts tested in this study[edit | edit source]

100968 100969

Photosensitizer[edit | edit source]

Ru(bpy)3 3,6-Diamino-10-methylacridinium 100971 Ir(ppy)3

Investigation[edit | edit source]

General details for the experimental setup: Conducted inside a 25 mL borosilicate culture tube with a stir bar, a rubber septum, and an aluminum crimped top. The reaction vessel contained 5 mL of CH3CN, 2 μM of the catalyst, 200 μM of the photosensitizer, 100 mM BIH (112 mg), and 1 M phenol (470 mg). The reaction tubes were sparged with CO2 for 10 min, followed by injection of a gaseous internal standard (0.1 mL of C2H6). The reactions were placed on a stirplate 13 cm from two Kessil blue LED lamps (440 nm) for 15 or 30 min at a time and maintained at ambient temperature using a fan. Analysis of the headspace by Gas Chromatography (GC).

catcat conc [µM]PSPS conc [mM]e-De-D conc [M]..solvent Aadditives..TON COTON H2..
1.

Molecule:100968

2

Ru(bpy)3

0.2

BIH

0.1

MeCN

1552086
2.

Molecule:100968

0.2

Ru(bpy)3

0.2

BIH

0.1

MeCN

303491013
3.


Ru(bpy)3

0.2

BIH

0.1

MeCN

4352
4.

Molecule:100968

2


BIH

0.1

MeCN

1120
5.

Molecule:100968

2

Ru(bpy)3

0.2


MeCN

1500
6.

Molecule:100968

2

Ru(bpy)3

0.2

BIH

0.1

MeCN

60
7.

Molecule:100968

2

Ru(bpy)3

0.2

BIH

0.1

MeCN

Ar0222
8.

Molecule:100968

2

Molecule:100971

0.2

BIH

0.1

MeCN

12749163
9.

Molecule:100968

0.2

Molecule:100971

0.2

BIH

0.1

MeCN

287126527
10.

Molecule:100968

2

Ir(ppy)3

0.2

BIH

0.1

MeCN

18502141
11.

Molecule:100968

2

Molecule:100970

0.2

BIH

0.1

MeCN

67100

The values in Table 2 include TOF numbers given in TON/min

Investigation-Name: Results Co2+ experiments taken from SI

Further Information[edit | edit source]

The results for the catalytic activity of the Co2+ compound 100969 in Table 2 were gained from the Supporting Information.

Sacrificial electron donor[edit | edit source]

In this study, the experiments were done with the sacrificial electron donor BIH (100508).

Additives[edit | edit source]

Different sources of protons were used, e.g. PhOH, TFE and 4-CHLOROPHENOL

Investigations

Tags

TagContains tags that describe the content of the page.: photocatalytic CO2 reduction (Ontology: voc4cat, OBOID: voc4cat:0000099), TagContains tags that describe the content of the page.: CO