Designing a general route for rational synthesis of a series or families of nanomaterials for emerging applications has become more and more fascinating and vital in the view of nanoscience and nanotechnology. Herein, we explore a general strategy for fabricating uniform nanocages of metal hydroxides (MHs) and metal oxides (MOs). A template-assisted route inspired by Pearson's hard and soft acid-base (HSAB) principle was employed for synthesizing MH nanocages via meticulous selection of the coordinating etchant as well as optimization of the reaction conditions. The concept of "coordinating etching" is successfully achieved in this work. This unique route shows potential in designing well-defined and high-quality MH nanocages with varying components, shell thicknesses, shapes, and sizes at room temperature. Consequently, porous MO nanocages can be obtained readily just through appropriate thermal treament of the respective MH nanocages. The overall strategy present in this work extends the application of the HSAB principle in nanoscience and offers a unqiue clue for rational fabrication of hollow (porous) and/or amorphous structures on the nanoscale, where these nanocages may present promising potential for various applications.

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Thermoelectric materials can be used as the active materials in thermoelectric generators and as Peltier coolers for direct energy conversion between heat and electricity. Apart from inorganic thermoelectric materials, thermoelectric polymers have been receiving great attention due to their unique advantages including low cost, high mechanical flexibility, light weight, low or no toxicity, and intrinsically low thermal conductivity. The power factor of thermoelectric polymers has been continuously rising, and the highest ZT value is more than 0.25 at room temperature. The power factor can be further improved by forming composites with nanomaterials. This article provides a review of recent developments on thermoelectric polymers and polymer composites. It focuses on the relationship between thermoelectric properties and the materials structure, including chemical structure, microstructure, dopants, and doping levels. Their thermoelectric properties can be further improved to be comparable to inorganic counterparts in the near future.

Stretchable electronic materials have drawn strong interest due to their important applications in areas such as bioelectronics, wearable devices, and soft robotics. The stretchable electrode is an integral unit of stretchable systems. Intrinsically c o n d u c t i v e p o l y m e r s s u c h a s p o l y ( 3 , 4ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) can have high mechanical flexibility and good biocompatibility. However, their electrical conductivity and mechanical stretchability should be greatly improved for its applications as the stretchable electrode. Here, we report highly conductive and highly stretchable PEDOT:PSS by incorporating biocompatible D-sorbitol. D-Sorbitol can serve as both the secondary dopant and plasticizer for PEDOT:PSS. It can not only significantly improve the conductivity but also the stretchability. D-Sorbitol-PEDOT:PSS (s-PEDOT:PSS) can have a conductivity of >1000 S/cm, and the conductivity could be maintained at a strain up to 60%. The resistance of s-PEDOT:PSS remains almost constant during repeated stretching−releasing cycles. The mechanism for the stretchability improvement by D-sorbitol is ascribed to the softening of PSSH chains. D-Sorbitol can position among the PSSH chains and thus destructs the hydrogen bonds among the PSSH chains. This makes the conformational change of the PSSH chains under stress become easy and thus increases the mechanical flexibility of PEDOT:PSS. This conductivity is the highest for biocompatible intrinsically conductive polymers with high stretchability.

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Hollow hierarchical CoO nanocube/reduced graphene oxide (COG) composite has been fabricated with the sacrificial-template method and the subsequent thermal treatment. Hollow/porous architectures supply high specific surface area and buffer the volume change during the lithium uptake/release processes, while rGO matrix ensures the system conductivity and further reinforces the structure. Serving as the anode material of lithium ion battery, COG demonstrates high lithium storage capacity, reaching 1170 mA h g–1 at a current density of 150 mA g–1, which is much higher than the capacity of rGO-free hollow CoO nanocubes. Ninety-four percent retention after 60 cycles further proves its stable cyclability. The combination of the advantages of the as-prepared befitting nanostructure and the rGO should be responsible for the durable rate behavior and the high capacity. Moreover, unfully reduced graphene oxide was achieved with the assistance of the multifunctional Na2S2O3, leading to more disorders and defects left in the composite and should also afford a positive influence on the lithium storage performance of the COG.

The incidence of isolated SMA dissection may not be as rare as previously reported. Endovascular treatment of isolated SMA dissection is commonly used in China as a first-line treatment.

Template-directed synthesized Fe0.1-Ni-MOF nanoarray (Fe0.1-Ni-MOF/NF) behaves efficiently as an electrocatalyst for alkaline water oxidation with a strong electrochemical durability.