Product selectivity for CO2 reduction

Patent metadata

Field	Value
Publication number	US-12091763-B2
Application number	US-202217836449-A
Country	US
Kind code	B2
Filing date	Jun 9, 2022
Priority date	Apr 10, 2017
Publication date	Sep 17, 2024
Grant date	Sep 17, 2024

Abstract

A CO 2 reduction system has a cathode in contact with a catholyte. The cathode includes a selectivity-determining layer on an electron conductor. The selectivity-determining layer includes a selectivity-determining component that includes a substituted heterocycle.

First claim

The invention claimed is:

1. A CO 2 reduction system, comprising:
a cathode in contact with a catholyte,
the cathode comprises an electron conductor of polycrystalline copper;
the catholyte comprises CO 2 , an additive, and a reduced form of the additive, wherein the additive and the reduced form of the additive make up a selectivity-determining component,
wherein the selectivity determining component is simultaneously electrodeposited on the electron conductor with the reduction of CO 2 to form a selectivity-determining layer, and wherein the selectivity-determining layer comprises a backbone of a substituted heterocycle.

2. The system of claim 1 , wherein the substituted heterocycle includes one or more nitrogen atoms in a ring structure.

3. The system of claim 1 , wherein a substituent on the substituted heterocycle includes an aryl group.

4. The system of claim 3 , wherein the aryl group is substituted.

5. The system of claim 1 , wherein the additive is positively charged.

6. The system of claim 1 , wherein the selectivity-determining component is selected from a group consisting of a dimer, an oligomer, and a polymer.

7. The system of claim 1 , wherein the substituted heterocycle is one of multiple substituted heterocycles included in the selectivity-determining component and the selectivity-determining component includes multiple units that each includes one or more of the substituted heterocycles.

8. The system of claim 7 , wherein the selectivity-determining component is represented by:

where different portions of R 1-9 are the same or different and individually represent an H, an alkyl group, an aryl group, a hydrocarbyl group, a halogen, an alkoxy group, a thiol, an aminyl group, a phosphorous-containing group, a silicon-containing group, and a boron-containing group.

9. The system of claim 6 , wherein the selectivity-determining component is represented by:

where L represents nil or an organic linker, n is greater than or equal to 1, R 21-27 individually represent an H, alkyl group, aryl group, hydrocarbyl group, halogen, alkoxy group, thiol, aminyl group, phosphorous-containing group, silicon-containing group, and a boron-containing group.

10. The system of claim 1 , wherein the additive is positively charged.

11. The system of claim 10 , wherein the additive is represented by

wherein R 1 represents an H, alkyl group, aryl group, hydrocarbyl group, halogen, alkoxy group, thiol, aminyl group, phosphorous-containing group, silicon-containing group, and a boron-containing group and R 2 represents an H, alkyl group, aryl group, hydrocarbyl group, halogen, alkoxy group, thiol, aminyl group, phosphorous-containing group, silicon-containing group, and a boron-containing group.

12. The system of claim 1 , wherein the selectivity-determining layer provides for selectivity of greater than 60% for C ≥2 hydrocarbon products.

13. The system of claim 1 , wherein the catholyte further comprises an electrolyte selected from KHCO 3 , KOH, NaHCO 3 , and NaOH.

14. The system of claim 1 , wherein a potential from −0.8 V and −1.3 vs. RHE is applied to the cathode.

15. A CO 2 reduction system, comprising:
a cathode in contact with a catholyte,
the cathode comprising an electron conductor of polycrystalline copper;
the catholyte including CO 2 and an additive, the additive including a positively charged substituted heterocycle; and
wherein a polymeric layer is formed on the electron conductor with the simultaneous reduction of CO 2 , and wherein the polymeric layer comprises a backbone of substituted heterocycles and is obtained from a reduced form of the additive.

16. The system of claim 15 , wherein the substituted heterocycle includes one or more nitrogen atoms in a ring structure.

17. The system of claim 16 , wherein the substituted heterocycle includes a substituent linked to one of the nitrogen atoms in the ring structure.

18. The system of claim 17 , wherein the substituent includes an aryl.

Assignees

• The California Institute Of Tech
• California Inst Of Techn

Inventors

• Han Zhiji
• Kortlever Ruud
• Chen Hsiang-Yun
• Peters Jonas C
• Agapie Theodor
• Rosas Hernandez Jorge A
• Thevenon Arnaud A

Classifications

• C25B11/075

  consisting of a single catalytic element or catalytic compound · CPC title

• C25B11/057

  consisting of a single element or compound · CPC title

• C25B11/051

  Electrodes formed of electrocatalysts on a substrate or carrier · CPC title

• C10K3/00 Primary

  Modifying the chemical composition of combustible gases containing carbon monoxide to produce an improved fuel, e.g. one of different calorific value, which may be free from carbon monoxide · CPC title

• C07C1/12

  from carbon dioxide with hydrogen · CPC title