|
|||||
|
|
Carboxylated PIM-1 incorporating sulfonated graphene oxide effectively improves the ion transport properties of the membrane |
|
| Authors: | Yuanhang Song Tao Wang Jingxian Zhang Yanhui Li Junru Li Chuanwei Zhang Pengfei Zhang |
| Affiliation: | 1. College of Mechanical and Electrical Engineering, Qingdao University, Qingdao, China;2. College of Mechanical and Electrical Engineering, Qingdao University, Qingdao, China
Contribution: Conceptualization (equal), Formal analysis (equal), Methodology (equal);3. College of Mechanical and Electrical Engineering, Qingdao University, Qingdao, China Contribution: Resources (equal), Software (equal);4. College of Mechanical and Electrical Engineering, Qingdao University, Qingdao, China Contribution: Project administration (equal), Supervision (equal);5. College of Mechanical and Electrical Engineering, Qingdao University, Qingdao, China Contribution: Formal analysis (equal), Supervision (equal);6. College of Mechanical and Electrical Engineering, Qingdao University, Qingdao, China Contribution: Formal analysis (equal), Investigation (equal) |
| Abstract: | This study explores the ion transport properties of self-microporous polymers by introducing a novel combination of carboxylated PIM-1 with sulfonated graphene oxide (SGO) to fabricate membranes. The resulting membranes exhibit enhanced structural stability, hydrophilicity, and ion exchange capacity (IEC) compared with the original carboxylated PIM-1 (CPIM-1), while preserving the subnanoporous structure. However, it was observed that excessive SGO loading leads to a detrimental “blocking effect” that compromises various membrane properties. Through electrically driven ion transport tests in a 0.01 M NaCl solution, it is demonstrated that a moderate amount of SGO effectively enhances membrane conductivity from 46.96 μS m−1 (for carboxylated PIM-1 membranes without SGO) to 56.55 μS m−1. Additionally, the membranes exhibit selective sieving of cations and anions. The presence of small-sized ion channels and the electrostatic repulsion generated by the abundant carboxyl and sulfonic acid groups significantly hinder Cl− transport. Consequently, the Na+/Cl− migration ratio (t+/t−) reaches 98 at a concentration ratio of 10:1 on both sides of the membrane, surpassing the value of 3.74 observed for the pure CPIM-1 membrane. This investigation provides valuable insights for the practical application of easily prepared, processable, and cost-effective hydrophilic self-contained microporous polymer membranes in ion transport applications. |
| Keywords: | electrical conductivity hydrophilic ion exchange membrane self-microporous polymers PIM-1 |