Polyelectrolyte membranes based on phosphorylated-PVA/cellulose acetate for direct methanol fuel cell applications: synthesis, instrumental characterization, and performance testing

Mahmoud Khalaf; Ahmed M Saeed; Ahmed I Ali; Elbadawy A Kamoun; Alaa Fahmy

doi:10.1038/s41598-023-40035-6

Polyelectrolyte membranes based on phosphorylated-PVA/cellulose acetate for direct methanol fuel cell applications: synthesis, instrumental characterization, and performance testing

Sci Rep. 2023 Aug 10;13(1):13011. doi: 10.1038/s41598-023-40035-6.

Authors

Mahmoud Khalaf¹, Ahmed M Saeed², Ahmed I Ali³, Elbadawy A Kamoun^{4

5}, Alaa Fahmy⁶

Affiliations

¹ Chemistry Department, Faculty of Science, Al-Azhar University, Cairo, Egypt.
² Chemistry Department, Faculty of Science, Al-Azhar University, Cairo, Egypt. ahmed_saeed@azhar.edu.eg.
³ Basic Science Department, Faculty of Technology and Education, Helwan University, Saray-El Qoupa, El Sawah Street, Cairo, 11281, Egypt.
⁴ Polymeric Materials Research Department, Advanced Technology and New Materials Research Institute (ATNMRI), City of Scientific Research and Technological Applications (SRTA-City), New Borg Al-Arab, 21934, Alexandria, Egypt.
⁵ Nanotechnology Research Center (NTRC), The British University in Egypt (BUE), El-Sherouk City, Cairo, 11837, Egypt.
⁶ Chemistry Department, Faculty of Science, Al-Azhar University, Cairo, Egypt. alaa.fahmy@azhar.edu.eg.

Abstract

Designing and synthesis of cost-effective and improved methanol permeable and proton conductive membranes are the main challenges for preparation of polymeric electrolyte membrane (PEM). Herein, a cost-effective PEM membrane based on phosphorylated polyvinyl alcohol (PVA)-grafted-cellulose acetate (CA) was prepared by a solution-casting technique. Water and methanol uptakes of phosphorylated PVA/CA membranes were characterized as function with the molar ratio of CA. Additionally, structure and morphology of phosphorylated PVA/CA (Ph-PVA/CA) membranes were verified by FT-IR analysis, SEM investigation. Furthermore, ion exchange capacity (IEC), proton conductivity and methanol permeation of Ph-PVA/CA membranes were examined based on the concentration of OPA basically. The results manifested a perceptible improvement in proton conductivity from 0.035 to 0.05 S/cm at 25 and 70 °C, respectively using 600 μL of OPA, and IEC of 2.1 meq/g using 400 μL of OPA at ambient temperature. On the other hand, methanol permeability (P = 1.08 × 10^-10 cm²/s) was lower than Nafion 117 admirably. The optimum OPA concentration was 200 μL according to conductivity measurements (at 10% PVA, 150 μL GA, and CA 7%). Finally, prepared Ph-PVA/CA membranes exhibited enhancement in critical natures such as proton conductivity and IEC combined with its low-cost materials, which make them excellent candidate as PEM for DMFCs application.