The Proton Conductivity and Mechanical Properties of SPEEK-Ce:Zr Nanocomposite Membrane

Abstract:

This study investigates the effect of ceria (CeO₂) and zirconia oxide (ZrO₂) nanoparticles on the sulfonated polyether ether ketone (SPEEK) membranes prepared by the solution casting method. The resulting SPEEK-Ce:Zr nanocomposite membranes were characterized by Fourier Transform Infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA). The tensile strength, ion exchange capacity (IEC), water uptake, and swelling ratio of the composite membrane were also investigated. The results showed that the composite membranes outperformed the pristine SPEEK membranes in terms of IEC, swelling ratio, and proton conductivity of up to 58 mS/cm at 25 °C. Furthermore, the performance improvement increased with the Ce:Zr loading ranging from 1 – 10%. The incorporation of metal oxide nanoparticles into the polymer matrix resulted in a more uniform distribution of the nanoparticles in the membrane matrix, with nearly no agglomeration, leading to improved mechanical strength and chemical stability. The composite membranes with enhanced properties thus show great potential for applications such as fuel cells.

• Periodical: Journal of Nano Research (Volume 93)
• Pages: 83-97
• DOI: https://doi.org/10.4028/p-9a4Ffa
• Online since: July 2026
• Authors: Mayetu Segale, Rudzani Sigwadi, Olayemi Jola Fakayode, Tumelo Seadira, Bakang Mothudi, Mantsopa Koena Zamisa*, Tau S. Ntelane, Touhami Mokrani
• Keywords: Ceria (CeO₂), Metal Oxides, Polymers, Proton Conductivity, SPEEK-Ce:Zr Composite Membrane, Sulfonated Polyether Ether Ketone (SPEEK), Zirconia Oxide (ZrO₂)

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