Evaluation of sulfonated chitosan-g-sulfonated polyvinyl alcohol/polyethylene oxide/ sulfated zirconia composite polyelectrolyte membranes for direct borohydride fuel cells: Solution casting against the electrospun membrane fabrication technique Marwa H. Gouda 1 , Noha A. Elessawy 2 *, Mohamed Elnouby 3 , Mohamed A. Ghorab 4 , Islam Othman Radwan 4 , Ali Hashim 5 , M. Elsayed Youssef 2 and Diogo M. F. Santos 6 * 1 Polymer Materials Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab, Egypt, 2 Computer Based Engineering Applications Department, Informatics Research Institute IRI, City of Scientific Research and Technological Applications City (SRTA-City), New Borg El-Arab, Egypt, 3 Nanomaterials and Composites Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab, Egypt, 4 Environmental Toxicology Lab, Marine Environment Department, National Institute of Oceanography and Fisheries (NIOF), New Borg El-Arab, Egypt, 5 Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab, Egypt, 6 Center of Physics and Engineering of Advanced Materials, Laboratory for Physics of Materials and Emerging Technologies, Chemical Engineering Department, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal To improve the mechanical properties of proton exchange membranes, consequently improving the performance of direct borohydride fuel cells, the present study prepared sulfonated chitosan-g-sulfonated polyvinyl alcohol/polyethylene oxide doped with sulfated zirconia composite (SCS-g- SPVA/PEO/SZrO 2 ) polyelectrolyte membranes. Two fabrication techniques were followed, solution casting and electrospinning, to have the membranes in film and fiber forms and study the effect of the different forms on the membrane’s physicochemical properties. For the casting technique, different concentrations of SZrO 2 (1-3 wt%) were used, while the optimum concentration of SZrO 2 (3 wt%) was used in the electrospun one (SCS-g- SPVA/PEO/SZrO 2 -CF). SCS-g-SPVA/PEO/SZrO 2 -C membranes were prepared in a single step. The grafting and the crosslinking were carried out using glutaraldehyde and sulfosuccinic acid as sulfonating agents for chitosan and PVA and coupling agents simultaneously using click chemistry. On the other hand, SCS-g-SPVA/PEO/SZrO 2 -CF membranes were prepared in two steps. They were fabricated with electrospinning and then dipped into the OPEN ACCESS EDITED BY Mazeyar Parvinzadeh Gashti, PRE Labs Inc., Canada REVIEWED BY Ji-Huan He, Soochow University, China Sadhasivam Thangarasu, Yeungnam University, South Korea *CORRESPONDENCE Noha A. Elessawy, nony_essawy@yahoo.com Diogo M. F. Santos, diogosantos@tecnico.ulisboa.pt SPECIALTY SECTION This article was submitted to Polymeric and Composite Materials, a section of the journal Frontiers in Materials RECEIVED 03 April 2022 ACCEPTED 06 July 2022 PUBLISHED 12 August 2022 CITATION Gouda MH, Elessawy NA, Elnouby M, Ghorab MA, Radwan IO, Hashim A, Youssef ME and Santos DMF (2022), Evaluation of sulfonated chitosan-g- sulfonated polyvinyl alcohol/ polyethylene oxide/sulfated zirconia composite polyelectrolyte membranes for direct borohydride fuel cells: Solution casting against the electrospun membrane fabrication technique. Front. Mater. 9:912006. doi: 10.3389/fmats.2022.912006 COPYRIGHT © 2022 Gouda, Elessawy, Elnouby, Ghorab, Radwan, Hashim, Youssef and Santos. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. Frontiers in Materials frontiersin.org 01 TYPE Original Research PUBLISHED 12 August 2022 DOI 10.3389/fmats.2022.912006