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Rotatable spacer increases the motions of ionic side-chain to accelerate both ion and H2O transport during fuel cell operation.

Alkaline polyelectrolyte fuel cell now receives growing attention as a promising candidate to serve as the next generation energy-generating device by enabling the use of non-precious metal catalysts (silver, cobalt, nickel et al.). However, the development and application of alkaline polyelectrolyte fuel cell is still blocked by the poor hydroxide conductivity of anion exchange membranes. In order to solve this problem, we demonstrate a methodology for the preparation of highly OH− conductive anion exchange polyelectrolytes with good alkaline tolerance and excellent dimensional stability. Polymer backbones were grafted with flexible aliphatic chains containing two or three quaternized ammonium groups. The highly flexible and hydrophilic multi-functionalized side chains prefer to aggregate together to facilitate the formation of well-defined hydrophilic-hydrophobic microphase separation, which is crucial for the superior OH− conductivity of 69 mS/cm at room temperature. Besides, the as-prepared AEMs also exhibit excellent alkaline tolerance as well as improved dimensional stability due to their carefully designed polymer architecture, which provide new directions to pursue high performance AEMs and are promising to serve as a candidate for fuel cell technology.

Highly alkaline stable imidazolium-type membrane has been developed for fuel cells by protection of the imidazolium ring at C2, C4 and C5 positions.

Biotransformation of lignin to lipids is challenging due to lignin’s recalcitrant nature as a phenolic heteropolymer with a nonuniform structure that imparts rigidity and recalcitrance of plant cell walls. In this study, wild and engineered Rhodococcus strains (R. opacus PD630 and R. jostii RHA1 VanA–) with lignin degradation and/or lipid biosynthesis capacities were selected to establish fundamental understanding of the pathways and functional modules necessary to enable a platform for biological conversion of biomass-derived lignin to lipids. Degradation of lignin (39.6%, dry weight) was achieved by performing cofermentation with wild type R. opacus PD630 and engineered R. jostii RHA1 VanA–. Co-fermentation of these two strains produced higher lipids yield than single strain fermentation. Profiles of metabolites produced by the Rhodococcus strains while growing on alkali technical lignin suggested that lignin was depolymerized to reactive intermediates, such as vanillin, 2,3-dihydro-benzofuran, 2-methoxy-4-vinylphenol, and 3-hydroxy-4-methoxy-benzaldehyde, for lipid biosynthesis. Additionally, fatty acids (C13–C24), especially palmitic acid (C16:0; 35.8%) and oleic acid (C18:1; 47.9%), were accumulated in cells of R. opacus PD630 and R. jostii RHA1 VanA– with lignin as the sole carbon source. Results suggest that the cofermentation strategy can depolymerize lignin into aromatics and promote the lipid production. The lipids produced during cofermentation of lignin by R. opacus PD630 and R. jostii RHA1 VanA– showed promising potential in biofuel production.

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The rechargeability of aqueous zinc metal batteries is plagued by parasitic reactions of the zinc metal anode and detrimental morphologies such as dendritic or dead zinc. To improve the zinc metal reversibility, hereby we report a new solution structure of aqueous electrolyte with hydroxyl-ion scavengers and hydrophobicity localized in solvent clusters. We show that although hydrophobicity sounds counterintuitive for an aqueous system, hydrophilic pockets may be encapsulated inside a hydrophobic outer layer, and a hydrophobic anode–electrolyte interface can be generated through the addition of a cation-philic, strongly anion-phobic, and OH–-reactive diluent. The localized hydrophobicity enables less active water and less absorbed water on the Zn anode surface, which suppresses the parasitic water reduction; while the hydroxyl-ion-scavenging functionality further minimizes undesired passivation layer formation, thus leading to superior reversibility (an average Zn plating/stripping efficiency of 99.72% for 1000 cycles) and lifetime (80.6% capacity retention after 5000 cycles) of zinc batteries.

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