Transporting protons is essential in several biological processes as well as in renewable energy devices, such as fuel cells. Although biological systems exhibit precise supramolecular organization of chemical functionalities on the nanoscale to effect highly efficient proton conduction, to achieve similar organization in artificial systems remains a daunting challenge. Here, we are concerned with transporting protons on a micron scale under anhydrous conditions, that is proton transfer unassisted by any solvent, especially water. We report that proton-conducting systems derived from facially amphiphilic polymers that exhibit organized supramolecular assemblies show a dramatic enhancement in anhydrous conductivity relative to analogous materials that lack the capacity for self-organization. We describe the design, synthesis and characterization of these macromolecules, and suggest that nanoscale organization of proton-conducting functionalities is a key consideration in obtaining efficient anhydrous proton transport.

A series of copolymers containing covalently attached benzophenone (BP) photo-cross-linkers were synthesized, and their UV-induced gelation was monitored as a function of the extent of BP conversion. For poly(methyl methacrylate) copolymers, the recombination yield between BP-and aliphatic-centered radicals was estimated and compared to that for dimerization of each species, directly confirming that the high gelation efficiencies observed for these copolymers arise due to the additional cross-linking pathways provided by covalently incorporated BP, as compared to doping with a small-molecule cross-linker. The placement of the hydrogen species most susceptible to abstraction by triplet benzophenone is found to greatly influence gelation efficiency, since radical generation on the polymer backbone typically increases the probability of dislinking events, while hydrogen abstraction pendent to the copolymer backbone tends to enhance cross-linking. Finally, the presence of atmospheric oxygen during photo-cross-linking was found to yield only modest changes in the gelation behavior of these copolymers.

In this communication, we show that liquid crystalline phases lower the activation energy barrier for proton transport. The liquid crystalline phases were obtained using a triphenylene core with alkyl chains bearing a triazole moiety at their termini.

In this communication, we introduce squaric acid derivatives as anhydrous proton conductors. We report the synthesis, characterization and proton conductivities of four squaric acid derivatives. The anhydrous proton conductivity of one of the derivatives was 2.3 × 10(-3) S cm(-1) at 110 °C, comparable to the conductivity of molten 1H-1,2,3-triazole or 1H-imidazole.

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