Navigating Excellence: A Comprehensive Review on the Versatile Potential of High-Performance N-Heterocyclic Triazole as an Electrolyte for Proton Exchange Membrane Fuel Cells

Proton exchange membrane fuel cells (PEMFCs) are a highly efficient energy producing device that stands as a novel approach to sort out the energy demand faced by the world. The proton exchange membrane plays a significant role for the function of PEMFCs. Possessing dual functional behavior for ease of proton transfer which other aromatic polymers fail to own naturally has made the triazole moiety a unique PEM material. The material's elevated self-dissociation capability, facilitating proton conduction, coupled with its high dielectric constant led to an increased demand for its application, highlighting its significance in various usage scenarios. For instance, by self-diffusion, 1H-1,2,3-triazole and 1H-1,2,4-triazole materials exhibited conductivities of 1.3 × 10–4 and 1.5 × 10–4 S/cm, respectively, in their pure forms. Various research groups utilize the triazole molecule as an ionic cross-linker, as a source for the introduction of functional groups, and as a dopant that eventually increases the proton conductivity. This review focuses on the advantages and different proton conduction processes that have been carried out in triazole materials like 1H-1,2,3-triazole, 1H-1,2,4-triazole, poly(1-vinyl-1,2,4-triazole), and the new originating sulfonated polytriazole.