Cellulose-based membranes for PEM fuel cells: Acidic durability and recent advances

Cellulose-based membranes have emerged as promising alternatives to traditional Nafion-based proton exchange membranes (PEMs) in fuel cell applications because of their sustainability, low cost, and biodegradability. This review explores recent advancements in the development of cellulose-based membranes, focusing on strategies such as chemical cross-linking, surface functionalization, and incorporation of various materials to enhance proton conductivity, mechanical strength, and chemical stability. These modifications have led to significant improvements in the performance of cellulose membranes, particularly under acidic and oxidative conditions typical in proton exchange membrane fuel cells (PEMFCs). However, challenges remain in terms of achieving long-term durability, scalability, and uniformity in membrane properties, especially when transitioning from laboratory-to industrial-scale production. This review also highlights the need for standardized, long-term durability testing to better understand the performance of cellulose-based membranes under real-world fuel-cell conditions. In the future, the successful commercialization of cellulose-based PEMs will require continued research focused on optimizing the membrane properties, enhancing scalability, and ensuring performance consistency. Interdisciplinary collaboration and innovative fabrication techniques are critical for advancing these membranes as viable and eco-friendly alternatives to conventional PEM.