The recharge ability of zinc metal‐based aqueous batteries is greatly limited by the zinc anode. The poor cycling durability of Zn anodes is attributed to the dendrite growth, shape change and passivation, but this issue has been ignored by using an excessive amount of Zn in the past. Herein, a 3D nanoporous (3D NP) Zn–Cu alloy is fabricated by a sample electrochemical‐assisted annealing thermal method combined, which can be used directly as self‐supported electrodes applied for renewable zinc‐ion devices. The 3D NP architectures electrode offers high electron and ion transport paths and increased material loading per unit substrate area, which can uniformly deposit/strip Zn and improve charge storage ability. Benefiting from the intrinsic materials and architectures features, the 3D NP Zn–Cu alloy anode exhibits high areal capacity and excellent cycling stability. Further, the fabricated high‐voltage double electrolyte aqueous Zn–Br2 battery can deliver maximum areal specific capacity of ≈1.56 mAh cm−2, which is close to the level of typical commercial Li‐ion batteries. The excellent performance makes it an ideal candidate for next‐generation aqueous zinc‐ion batteries.

High density polyethylene (HDPE) was molded by a new polymer processing method, that is, water‐assisted injection molding (WAIM), and its hierarchical structure was studied by two‐dimensional small angle X‐ray scattering (SAXS). For comparison, the hierarchical structure of HDPE molded by conventional injection molding (CIM) was also characterized. The result shows that the WAIM part exhibits a distinct skin‐core‐water channel structure which is different from the skin‐core structure for the CIM part. In the skin layer of both WAIM and CIM parts, the shish‐kebab structure was formed due to the shear stress brought by melt filling, but the lamellar orientation parameter of CIM part is smaller than that of WAIM part. The spherulites with random lamellar orientation are dominant at the core of both parts owing to the low cooling rate and feeble shear stress therein. Interestingly, the shish structure and the lamellae with low level of orientation can be found at the water channel layer of WAIM part. They are attributed to the shear stress brought by water penetration. Moreover, the lamellar orientation parameter in water channel layer is smaller than that of skin layer. In addition, the long period of WAIM part first increases and then decreases with the elevating distance from the skin surface, while that of CIM part tends to increase monotonously. In a word, one can conclude that the rapid cooling rate and shear brought by the injected water have significant influence on the structural evolution for the WAIM part. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

To meet the increasing requirement of flexible energy storage devices, it is critical to develop an electrode with commercial-level mass loading of active material for supercapacitors. Herein, we fabricated a...

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Neutral Zn-air batteries (ZABs) have attracted much attention due to the enhanced lifespan and stability. However, their development is suppressed by the poor catalytic properties of the air-electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Hence, the exploration of highly efficient electrocatalysts for neutral ZABs is critical. Herein, we designed an economical heterostructure of Pt nanoparticle-modified Zn nanoplates (Pt/Zn NPs). Compared with commercial Pt/C electrocatalyst, our Pt/ Zn heterostructure exhibits comparable catalytic properties and ultrahigh stability in neutral media. The heterostructure can reduce the dosage of Pt and offer sufficient active sites, resulting in enhanced catalytic properties for ORR/OER in neutral media. When applied to neutral ZABs as air cathode, our heterostructure exhibits a high power density of 45 mW cm −2 and excellent stability of more than 850 cycles with negligible decay, making it the most efficient and robust one in neutral electrolyte. This approach opens a new avenue to strategically design catalysts with high activity for neutral ZABs, rendering them potential in portable and wearable electronic devices.

Polyamide 66 (PA 66) nanofiber bundles were first electrospun and then introduced into isotactic polypropylene (iPP) melts to prepare nanofiber bundle/iPP composites. To reveal the influences of matrix molecular weight (M n ) on the transcrystalline layer, three kinds of iPP with different M n were adopted. Polarized optical microscope was employed to investigate the transcrystallinity. In the presence of PA 66 nanofiber bundle, the heterogeneous nucleation distinctly happened in iPP melts. Moreover, the higher the iPP M n , the denser the nuclei. Both a decrease in matrix M n and an increase in isothermal crystallization temperature led to an increase in the induction time. The maximum temperature at which the transcrystalline layer can be optically observed increased with the increase of M n . The growth rate of transcrystallinity decreased with the increasing M n and crystallization temperature. Moreover, selective melting of the transcrystalline layers confirmed that it was merely composed of α form crystal for all composites.

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