Radiation-grafted anion-exchange membranes: key features for enhanced water electrolysis

Author(s)

Biancolli, Ana Laura G. ; Chen, Binyu ; Menandro, Alessandra S. ; Fonseca, Fabio C. ; Santiago, Elisabete I. ; Holdcroft, Steven

• Document type: Journal article
• Source: JOURNAL OF MATERIALS CHEMISTRY A; v. 12, n. 32, p. 13-pg., 2024-07-15.

Abstract

Tailored, radiation-induced grafted anion-exchange membranes (RIG-AEMs) are incorporated in anion-exchange membrane water electrolyzers. Fabrication parameters of the polymeric electrolyte directly impact the performance of electrochemical devices. The effect of radiation absorbed dose, polymer type (low-density polyethylene (LDPE) or ethylene-tetrafluoroethylene (ETFE)), and polymer film thickness on current-voltage characteristics is studied. The radiation absorbed doses and the polymer thickness influence the degree of grafting (DoG) and ion-exchange capacity (IEC) of the synthesized membranes, which are correlated to their ionic conductivity and dimensional stability. The in operando electrochemical characterization in single cell electrolyzers, utilizing stainless steel felt as a combined anode catalyst and porous transport layer, required voltages as low as 1.78 V at 1 A cm-2 in 1 M KOHaq at 60 degrees C. LDPE-based RIG-AEMs were found more durable than ETFE-based RIG-AEMs over a 100 h period at a constant current density of 0.5 A cm-2 (voltage increase of 71 mu V h-1 for L-50-30 AEM vs. 300 mu V h-1 for E-25-20 AEM). These results provide valuable insights into the tradeoff between performance and durability of AEM water electrolyzers to guide the development of RIG-AEMs for water electrolysis applications. Progress in understanding crucial properties of radiation-induced grafted anion-exchange membranes (RIG-AEMs) to improve the performance and durability of water electrolysis systems. (AU)

• FAPESP's process: 19/26955-3 - Synthesis of anion exchange membranes and ionomers for application in electrochemical conversion devices
• Grantee: Ana Laura Gonçalves Biancolli
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 21/14786-2 - Highly stable anion exchange membranes: synthesis and electrochemical applications
• Grantee: Ana Laura Gonçalves Biancolli
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 17/11937-4 - A sustainable path to methane conversion by advanced electrochemical technologies
• Grantee: Fabio Coral Fonseca
• Support Opportunities: Research Grants - Research Centers in Engineering Program