Transition‐metal sulfides have gained considerable attention for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in rechargeable Zn‐air batteries owing to their natural abundance, chemical stability, and efficient activity. Here, cobalt sulfide nanocrystalline supported on the 3D hierarchically flower‐like porous nanocarbon (mC‐CoSx‐50) electrocatalysts have been synthesized through a combination of metal‐organic complexation and porous silica templates for efficient bifunctional oxygen catalysis. With the high specific surface area, high nitrogen content and heteroatom doping, the as‐synthesized mC‐CoSx‐50 exhibits an excellent bifunctional oxygen catalytic performance. Remarkably, the rechargeable Zn‐air batteries assembled with the cobalt sulfide‐based hierarchically porous electrocatalysts reveal a high peak power density and excellent cycling stability in comparison with Pt/C+RuO2 owing to the synergistic effects between cobalt sulfide nanocrystallines and hierarchically porous carbon. We envision that this work not only offers high‐performance metal sulfide for future clean energy conversion but also provides a facial strategy for constructing hierarchically porous carbon‐supported catalyst.

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Purpose -The purpose of this paper is to modify the photostability of organic fluorescent dyes and to develop and evaluate a route of their derived polymeric fluorescent dyes. Design/methodology/approach -A series of novel polymeric fluorescent dyes were prepared using 3-(2-benzimidazolyl)-7-(diethylamino)-coumarin (disperse yellow 8GFF, abbreviated as 8GFF) and polyethylene glycol (PEG) as raw materials. First, an intermediate of carboxyl functioned 8GFF was prepared by condensation reaction of 8GFF and pyromellitic dianhydride; and then the polymeric fluorescent dyes were synthesized by reacting PEG with the condensate intermediate. Findings -FTIR, UV-vis, and PL showed that the polymeric fluorescent dyes had been successfully synthesised, and the photostability of organic fluorescent dyes was improved significantly. Research limitations/implications -In the present work, the polymeric fluorescent dyes had been successfully synthesized, and the photostability of organic fluorescent dyes was improved significantly. This methodology can be employed to prepare novel polymeric fluorescent materials and to improve the photostability of organic dyes for various applications. Practical implications -Polycondensable dyes offer a new area of material science which can be widely used in coloured polymer materials production. Originality/value -The method developed in the study reported in this paper provided a new strategy to develop new types of polycondensable dyes materials with fluorescent property.

Honeycomb patterned hybrid films were prepared from sulfonated polystyrene (SPS) and tetrabutyl titanate (TBT) by a combination of the “breath figure” technique with a gelation process. The influences of solvents, concentration and the mass ratio of SPS/TBT in the hybrid sols on the morphology of the honeycomb films were investigated. The results from SEM, FTIR, DSC, TG and XRD showed that well-ordered films were formed when benzene was used as solvent, the mass ratios of SPS/TBT in the range of 10/1∼1/2 and the concentration of SPS maintained in the range of 20-80 mg/mL.

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