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The review is devoted to key problems in the development of modern proton‐conducting membranes for hydrogen power assuming its progress for using in fuel cells working at enhanced temperatures without catalysts poisoning and providing stable high proton conductivity and improved mechanical properties. Modern trends in the synthesis approaches such as application of emulsion polymerization and novel efforts for the modification of polymer membranes by chemically stable nanoparticles, carrying protons, are discussed as compared to commercially used membrane materials such as Nafion and Aquivion. The crucial role of advanced structural methods to recognize subtle features of molecular ordering and formation of conducting channels in membranes is considered, focusing on neutron scattering as the most powerful instrument for the analysis of ionomers and other nanoscale structures by means of selective isotopic contrasting structural elements in membrane materials. The integration of novel methods of emulsion polymerization and use of nanodiamonds and other nanoparticles embedded into polymer matrices is prospective in the creation of new generations of membrane materials with higher functional properties.

Purpose: Testing the potential use of saline suspension of polyvinylpyrrolidone (PVP)-coated gadolinium(Gd)-grafted detonation nanodiamonds (DND) as a novel contrast agent in MRI. Methods: Stable saline suspensions of highly purified de-agglomerated Gd-grafted DND particles coated by a PVP protective shell were prepared. T 1 and T 2 proton relaxivities of the suspensions with varying gadolinium concentration were measured at 8 Tesla. A series of ex vivo (phantom) and in vivo dynamic scans were obtained in 3 Tesla MRI using PVP-coated Gd-grafted DND and gadoterate meglumin in equal concentrations of gadolinium, and then T 1 -weighted hyperintensity was compared. Results: The proton relaxivities of PVP-coated Gd-grafted DND were found to be r 1 = 15.9 ± 0.8 s −1 mM −1 and r 2 = 262 ± 15 s −1 mM −1 , respectively, which are somewhat less than those for uncoated Gd-grafted DND but still high enough. Ex vivo MRI evaluation of PVP-coated Gd-grafted DND results with a dose-dependent T 1 -weighted hyperintensity with a significant advantage over the same for gadoterate meglumin. The same was found when the 2 contrast agents were tested in vivo. Conclusion:The novel MRI contrast agent -saline suspensions of PVP-coated Gd-grafted DND -provides significantly higher signal intensities than the common tracer gadoterate meglumin, therefore increasing its potential for a safer use in clinics.