Recent Progress in Covalent Organic Frameworks for Cathode Materials
Covalent organic frameworks (COFs) are constructed from small organic molecules through reversible covalent bonds, and are therefore considered a special type of polymer. Small organic molecules are divided into nodes and connectors based on their roles in the COF’s structure. The connector generall...
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-03-01
|
| Series: | Polymers |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4360/16/5/687 |
| _version_ | 1797263930779762688 |
|---|---|
| author | Chi Wang Yuchao Tian Wuhong Chen Xiaochun Lin Jizhao Zou Dongju Fu Xiao Yu Ruling Qiu Junwei Qiu Shaozhong Zeng |
| author_facet | Chi Wang Yuchao Tian Wuhong Chen Xiaochun Lin Jizhao Zou Dongju Fu Xiao Yu Ruling Qiu Junwei Qiu Shaozhong Zeng |
| author_sort | Chi Wang |
| collection | DOAJ |
| description | Covalent organic frameworks (COFs) are constructed from small organic molecules through reversible covalent bonds, and are therefore considered a special type of polymer. Small organic molecules are divided into nodes and connectors based on their roles in the COF’s structure. The connector generally forms reversible covalent bonds with the node through two reactive end groups. The adjustment of the length of the connector facilitates the adjustment of pore size. Due to the diversity of organic small molecules and reversible covalent bonds, COFs have formed a large family since their synthesis in 2005. Among them, a type of COF containing redox active groups such as –C=O–, –C=N–, and –N=N– has received widespread attention in the field of energy storage. The ordered crystal structure of COFs ensures the ordered arrangement and consistent size of pores, which is conducive to the formation of unobstructed ion channels, giving these COFs a high-rate performance and a long cycle life. The voltage and specific capacity jointly determine the energy density of cathode materials. For the COFs’ cathode materials, the voltage plateau of their active sites’ VS metallic lithium is mostly between 2 and 3 V, which has great room for improvement. However, there is currently no feasible strategy for this. Therefore, previous studies mainly improved the theoretical specific capacity of the COFs’ cathode materials by increasing the number of active sites. We have summarized the progress in the research on these types of COFs in recent years and found that the redox active functional groups of these COFs can be divided into six subcategories. According to the different active functional groups, these COFs are also divided into six subcategories. Here, we summarize the structure, synthesis unit, specific surface area, specific capacity, and voltage range of these cathode COFs. |
| first_indexed | 2024-04-25T00:20:50Z |
| format | Article |
| id | doaj.art-2a46417379c7469991be1f344964ee07 |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-04-25T00:20:50Z |
| publishDate | 2024-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-2a46417379c7469991be1f344964ee072024-03-12T16:53:42ZengMDPI AGPolymers2073-43602024-03-0116568710.3390/polym16050687Recent Progress in Covalent Organic Frameworks for Cathode MaterialsChi Wang0Yuchao Tian1Wuhong Chen2Xiaochun Lin3Jizhao Zou4Dongju Fu5Xiao Yu6Ruling Qiu7Junwei Qiu8Shaozhong Zeng9College of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaCollege of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaCollege of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaCollege of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaShenzhen Key Laboratory of Special Functional Materials & Shenzhen Engineering Laboratory for Advance Technology of Ceramics, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, ChinaCollege of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaCollege of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaCollege of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaCollege of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaCollege of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, ChinaCovalent organic frameworks (COFs) are constructed from small organic molecules through reversible covalent bonds, and are therefore considered a special type of polymer. Small organic molecules are divided into nodes and connectors based on their roles in the COF’s structure. The connector generally forms reversible covalent bonds with the node through two reactive end groups. The adjustment of the length of the connector facilitates the adjustment of pore size. Due to the diversity of organic small molecules and reversible covalent bonds, COFs have formed a large family since their synthesis in 2005. Among them, a type of COF containing redox active groups such as –C=O–, –C=N–, and –N=N– has received widespread attention in the field of energy storage. The ordered crystal structure of COFs ensures the ordered arrangement and consistent size of pores, which is conducive to the formation of unobstructed ion channels, giving these COFs a high-rate performance and a long cycle life. The voltage and specific capacity jointly determine the energy density of cathode materials. For the COFs’ cathode materials, the voltage plateau of their active sites’ VS metallic lithium is mostly between 2 and 3 V, which has great room for improvement. However, there is currently no feasible strategy for this. Therefore, previous studies mainly improved the theoretical specific capacity of the COFs’ cathode materials by increasing the number of active sites. We have summarized the progress in the research on these types of COFs in recent years and found that the redox active functional groups of these COFs can be divided into six subcategories. According to the different active functional groups, these COFs are also divided into six subcategories. Here, we summarize the structure, synthesis unit, specific surface area, specific capacity, and voltage range of these cathode COFs.https://www.mdpi.com/2073-4360/16/5/687COFsbatteriescathodeactive sitessynthesisreview |
| spellingShingle | Chi Wang Yuchao Tian Wuhong Chen Xiaochun Lin Jizhao Zou Dongju Fu Xiao Yu Ruling Qiu Junwei Qiu Shaozhong Zeng Recent Progress in Covalent Organic Frameworks for Cathode Materials Polymers COFs batteries cathode active sites synthesis review |
| title | Recent Progress in Covalent Organic Frameworks for Cathode Materials |
| title_full | Recent Progress in Covalent Organic Frameworks for Cathode Materials |
| title_fullStr | Recent Progress in Covalent Organic Frameworks for Cathode Materials |
| title_full_unstemmed | Recent Progress in Covalent Organic Frameworks for Cathode Materials |
| title_short | Recent Progress in Covalent Organic Frameworks for Cathode Materials |
| title_sort | recent progress in covalent organic frameworks for cathode materials |
| topic | COFs batteries cathode active sites synthesis review |
| url | https://www.mdpi.com/2073-4360/16/5/687 |
| work_keys_str_mv | AT chiwang recentprogressincovalentorganicframeworksforcathodematerials AT yuchaotian recentprogressincovalentorganicframeworksforcathodematerials AT wuhongchen recentprogressincovalentorganicframeworksforcathodematerials AT xiaochunlin recentprogressincovalentorganicframeworksforcathodematerials AT jizhaozou recentprogressincovalentorganicframeworksforcathodematerials AT dongjufu recentprogressincovalentorganicframeworksforcathodematerials AT xiaoyu recentprogressincovalentorganicframeworksforcathodematerials AT rulingqiu recentprogressincovalentorganicframeworksforcathodematerials AT junweiqiu recentprogressincovalentorganicframeworksforcathodematerials AT shaozhongzeng recentprogressincovalentorganicframeworksforcathodematerials |