It is very promising to introduce diazonium moiety into Nafion monomer based Diazonium (Perfluoroalkyl) Arylsufonylimide (PFSI) monomers for further polymerization and chemical grafting onto carbon electrodes as innovative electrolyte materials in the Proton Exchange Membrane (PEM) fuel cells. The PFSI polymers, more proton conductive and stable at high temperatures, can dramatically increase the stability and lifetime of the PEM fuel cells, compared to widely used perfluorosulfuric acid (PFSA) polymers. This paper presents such a straightforward methodology to optimally construct a new nation based diazonium PFSI monomer analogue, 2-diazonium 4-(trifluoromethyl) perfluoro-3, 6-dioxa-4-methyl-7-octene benzenesulfonylimide II. New approaches have been investigated to dramatically increase the percent yield for another monomer I, 4-diazonium perfluoro-3, 6-dioxa-4-methyl-7-octene benzenesulfonylimide. The thermal stability of the two monomer analogues then have been measured and compared. Another monomer analogue, 4-diazonium-3-fluoro perfluoro-3, 6-dioxa-4-methyl-7-octene benzenesulfonylimide III, has been attempted and discussed. Copyright (C) 2016, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.