The zinc-ion battery (ZIB) is a novel energy storage device, an attractive alternative to the lithium-ion battery. The frequently used aqueous electrolyte suffers from many problems such as zinc dendrites and leakage, which prompts hydrogel electrolytes and solid electrolytes as good replacements. However, hydrogel electrolytes are usually unstable, owing to water volatilization. Herein, a novel solid polymer electrolyte (SPE) utilizing coordination of zinc ions is designed and then introduced into an all-solid ZIB. Benefiting from the unique coordination structure between the polymer and zinc ions, the SPE shows outstanding flexibility, high ion conductivity, and self-healing properties. In addition, the imine bonds in the polymer allow the electrolyte to degrade in acid environments, endowing its recyclability. More importantly, solid-state ZIBs based on the polymer electrolytes exhibit an impressive cycling stability (125% capacity retention after 300 cycles) and a high coulombic efficiency (94% after 300 cycles). The results demonstrate the promising potentials of the developed SPEs that can be used in all-solid ZIBs.

Strong interchain interactions of conjugated polymers usually result in poor miscibility with molecular dopants, limiting the doping efficiency because of uncontrolled phase separation. We have developed a strategy to achieve efficient charge-transport and high doping miscibility in n-doped conjugated polymers. We solve the miscibility issue through disorder side-chains containing dopants better. Systemic structural characterization reveals a farther side-chain branching point will lead to higher disorders, which provides appropriate sites to accommodate extrinsic molecular dopants without harming original chain packings and charge-transport channels. Therefore, better sustainability of solidstate microstructure is obtained, yielding a stable conductivity even when overloading massive dopants. This work highlights the importance of realizing high host-dopant miscibility in molecular doping of conjugated polymers.

A series of block copolymers (BCPs) with a polynorbornene backbone containing short poly(ethylene oxide) (PEO) side chains and rigid side chains were synthesized by tandem ring-opening metathesis polymerization (ROMP). The contents of PEO in the BCPs are regulated by the degrees of polymerization (DPs) of main chains. The crystallization of the PEO side chains is suppressed. Confirmed by small-angle X-ray scattering (SAXS) results, the BCPs doped with lithium salt and ionic liquid self-assemble into lamellar (LAM) or hexagonally packed cylindrical (HEX) nanostructures that remain stable up to 200 °C. The ionic conductivity (σ) values of the complexes with an optimized doping ratio are above the order of 1 × 10 −4 S/cm over the temperature range of −25 to 200 °C, and the highest is 6.41 × 10 −3 S/cm at 200 °C, reaching the top level for PEO-based polymer electrolytes at high temperatures. In addition, the results of shear rheological experiments indicate that the thermally stable electrolyte membranes can maintain the solid state up to 200 °C. These BCP electrolytes with high σ values and excellent thermal stability in a wide temperature range may be applied in high-temperature lithium-ion batteries.

By combining reversible addition–fragmentation chain transfer (RAFT) with postfunctionalization and ion exchange, we synthesized a series of block copolymers (BCPs) containing an azobenzene-based liquid crystalline (LC) polymer (PAzo) and an imidazolium-containing poly­(ionic liquid) (PIL, PVB­(TFSI)) with the volume fraction of PIL (f PIL) values ranging from 15.9% to 69.9%. The samples obtained self-assemble into hexagonally packed cylinders (HEX), lamellae (LAM), and the mixed phase with coexisting HEX and LAM. The thin-film self-assembly of the samples PAzo101-b-PVB­(TFSI)22 and PAzo101-b-PVB­(TFSI)67 was studied systematically. We investigated the assembled structures of the thin films with various initial thicknesses after thermal annealing (145 °C for 12 h) or mixed solvent vapor annealing with tetrahydrofuran and n-hexane. Thin films with large-scale uniaxial PIL nanocylinders were obtained, which will greatly broaden the application of IL-based BCPs. Inverse phases were also observed for the thin films with thicknesses less than ∼120 nm. The different mechanisms of the formation of inverse nanostructures formed in the thinner films under the thermal annealing and mixed solvent vapor annealing conditions were also elucidated.

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The aggregation behaviors of conjugated polymers significantly influence their performance in solution-processed optoelectrical devices. Traditionally, the formation of aggregates from the self-assembly of conjugated polymers is considered as a thermodynamic equilibrium process. The abundant degree of conformation freedom of conjugated polymers might lead to complex aggregation behaviors in solution. However, the energy landscape of conjugated polymers during aggregation has rarely been studied before, which would provide the energetic and structural information about different aggregates. Our work tried to unravel the energy landscape of conjugated polymers during aggregation and investigate the energetic and structural information of the thermodynamically and kinetically stable aggregates in solution. Herein, kinetically and thermodynamically stable aggregates of naphthalene diimide (NDI)-based polymers are obtained through rational molecular design and thermodynamic control. Investigation of the theoretical calculation, photophysical properties, and morphologies of the conjugated polymers demonstrates the formation of and differences between kinetically and thermodynamically stable aggregates. The energetic and structural analysis of kinetically and thermodynamically stable aggregates here provide insight into the relations among the structure, morphology, and properties of conjugated polymers at the molecular level. This work demonstrates the energy landscape of conjugated polymers during aggregation and further extends our understanding of the aggregation mechanisms.

A white-light-emitting ion gel composed of a poly [(2-(4vinylphenyl)ethene-1,1,2-triyl)tribenzene-b-ethylene glycol-b-(2-(4-vinylphenyl)ethene-1,1,2-triyl)tribenzene] aggregation-induced emission (AIE) network and a poly([2,2′:6′,2″-terpyridin]-4′-yl methacrylate-co-methyl methacrylate) Eu 3+doped network was fabricated via a solution mixing process. This ion gel exhibits special multistimuli-responsive properties, and it can change its luminescent color by changing pH, temperature, or the solvent. The unique color-changing property is attributed to the different luminescent mechanisms of the AIE/Eu 3+ -doped polymer networks. The former is affected by changes in its aggregation state, while the latter is controlled by the dynamic metal−ligand cross-linking bonds. Furthermore, owing to the interpenetrating networks formed by the two polymers, the hybrid gel has both good mechanical strength and flexibility. It may be used in the fields of sensors, probes, and light-emitting materials.

a b s t r a c tA novel series of cobalt-free dense oxygen-permeable dual-phase membranes with a composition of 60 wt% Ce 0.8 Sm 0.2 O 2 À δ and 40 wt% Ba 0.95 La 0.05 Fe 1 À x Zr x O 3 À δ (SDC-BLFZ, x ¼0-0.20) are successfully developed and systematically evaluated as potential oxygen transport membranes for oxy-fuel combustion. The effects of substituting zirconium for iron on the structural characteristics, oxygen permeability, and CO 2 resistance of these membranes are studied. Experimental results show that appropriate doping of zirconium slightly decreases the oxygen permeability of the SDC-BLFZ membranes under helium but significantly enhances the structural stability and CO 2 tolerance. For the sample with x ¼0.15, a stable oxygen permeation flux of 0.24 ml min À 1 cm À 2 was achieved at 925 1C for a 1.0 mm thick membrane with CO 2 as the sweep gas for more than 80 h. This flux value is only 19% lower than that under an air/He gradient, which is much better than that obtained with most alkaline-metalcontaining composite dual-phase membranes. The enhanced CO 2 tolerance of the Zr-doped SDC-BLFZ membranes is attributed to the declining basicity of BLFZ induced by the substitution of Fe by Zr, as revealed by X-ray photoelectron spectroscopy (XPS). The stable oxygen permeability of the SDC-BLFZ membranes under CO 2 demonstrates the potential application of SDC-BLFZ in oxy-fuel combustion technology.