Low-dimensional ZnO nanocrystals with controlled size, aspect ratio, and oxygen defects (e.g., type and concentration) are successfully prepared through simple solvothermal and thermal treatment methods. The structure of the as-synthesized samples is characterized by XRD, N2 physical adsorption, TEM, and IR and XPS spectra. The results show that the aspect ratio and size of the as-synthesized ZnO nanocrystals increase with increasing [OH-]/[Zn2+]; the morphology evolves from nanorod to nanoparticle with an increase in the annealing temperature; the BET surface areas of the corresponding samples decrease during these processes, respectively; and different oxygen defects, which are likely to be oxygen vacancy (Vo**) and interstitial oxygen (Oi''), are formed in our experiments accordingly. With evolution of the structure, IR absorption bands and visible photoluminescence emission peaks of the synthesized ZnO nanocrystals shift and split, which is ascribed to the change of oxygen defects. In addition, it is found that the photocatalytic activity of the synthesized ZnO nanocrystals is mainly dependent on the type and concentration of oxygen defects. The relationship of structure-property and the possible photocatalytic mechanism are discussed in detail.

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Spider silk is one of the most robust natural materials, which has extremely high strength in combination with great toughness and good elasticity. Inspired by spider silk but beyond it, a healable and recyclable supramolecular elastomer, possessing superhigh true stress at break (1.21 GPa) and ultrahigh toughness (390.2 MJ m−3), which are, respectively, comparable to and ≈2.4 times higher than those of typical spider silk, is developed. The elastomer has the highest tensile strength (ultimate engineering stress, 75.6 MPa) ever recorded for polymeric elastomers, rendering it the strongest and toughest healable elastomer thus far. The hyper‐robust elastomer exhibits superb crack tolerance with unprecedentedly high fracture energy (215.2 kJ m−2) that even exceeds that of metals and alloys, and superhigh elastic restorability allowing dimensional recovery from elongation over 12 times. These extraordinary mechanical performances mainly originate from the meticulously engineered hydrogen‐bonding segments, consisting of multiple acylsemicarbazide and urethane moieties linked with flexible alicyclic hexatomic spacers. Such hydrogen‐bonding segments, incorporated between extensible polymer chains, aggregate to form geometrically confined hydrogen‐bond arrays resembling those in spider silk. The hydrogen‐bond arrays act as firm but reversible crosslinks and sacrificial bonds for enormous energy dissipation, conferring exceptional mechanical robustness, healability, and recyclability on the elastomer.

Separators play a pivotal role in the electrochemical performance and safety of lithium-ion batteries (LIBs). The commercial microporous polyolefin-based separators often suffer from inferior electrolyte wettability, low thermal stability, and severe safety concerns. Herein, a novel kind of highly flexible and porous separator based on hydroxyapatite nanowires (HAP NWs) with excellent thermal stability, fire resistance, and superior electrolyte wettability is reported. A hierarchical cross-linked network structure forms between HAP NWs and cellulose fibers (CFs) via hybridization, which endows the separator with high flexibility and robust mechanical strength. The high thermal stability of HAP NW networks enables the separator to preserve its structural integrity at temperatures as high as 700 °C, and the fire-resistant property of HAP NWs ensures high safety of the battery. In particular, benefiting from its unique composition and highly porous structure, the as-prepared HAP/CF separator exhibits near zero contact angle with the liquid electrolyte and high electrolyte uptake of 253%, indicating superior electrolyte wettability compared with the commercial polyolefin separator. The as-prepared HAP/CF separator has unique advantages of superior electrolyte wettability, mechanical robustness, high thermal stability, and fire resistance, thus, is promising as a new kind of separator for advanced LIBs with enhanced performance and high safety.

A highly flexible and nonflammable inorganic hydroxyapatite (HAP) paper made from HAP ultralong nanowires is reported. The paper can be used for printing and writing and is promising for the permanent and safe storage of information, such as archives and important documents. The HAP paper is also an excellent and recyclable adsorbent for organic pollutants.

GALAMOST [graphics processing unit (GPU)-accelerated large-scale molecular simulation toolkit] is a molecular simulation package designed to utilize the computational power of GPUs. Besides the common features of molecular dynamics (MD) packages, it is developed specially for the studies of self-assembly, phase transition, and other properties of polymeric systems at mesoscopic scale by using some lately developed simulation techniques. To accelerate the simulations, GALAMOST contains a hybrid particle-field MD technique where particle–particle interactions are replaced by interactions of particles with density fields. Moreover, the numerical potential obtained by bottom-up coarse-graining methods can be implemented in simulations with GALAMOST. By combining these force fields and particle-density coupling method in GALAMOST, the simulations for polymers can be performed with very large system sizes over long simulation time. In addition, GALAMOST encompasses two specific models, that is, a soft anisotropic particle model and a chain-growth polymerization model, by which the hierarchical self-assembly of soft anisotropic particles and the problems related to polymerization can be studied, respectively. The optimized algorithms implemented on the GPU, package characteristics, and benchmarks of GALAMOST are reported in detail.

Monodisperse Fe(3)O(4) and γ-Fe(2)O(3) magnetic mesoporous microspheres are prepared via a surfactant-free solvothermal combined with precursor thermal transformation method. The as-prepared Fe(3)O(4) and γ-Fe(2)O(3) magnetic mesoporous microspheres have a relatively high specific surface area of 122.3 and 138.6 m(2)/g, respectively. The Fe(3)O(4) and γ-Fe(2)O(3) magnetic mesoporous microspheres are explored as the anode materials for lithium-ion batteries, and they have a high initial discharge capacity of 1307 and 1453 mA h/g, respectively, and a good reversible performance (450 mA h/g for Fe(3)O(4) and 697 mA h/g for γ-Fe(2)O(3) after 110 cycles) at the current density of 0.2C.

To build a sustainable society, it is of significant importance but highly challenging to develop remalleable, healable, and biodegradable polymeric materials with integrated high strength and high toughness. Here, we report a superstrong and ultratough sustainable supramolecular polymeric material with a toughness of ca. 282.3 J g −1 (395.2 MJ m −3 ) in combination with a tensile strength as high as ca. 104.2 MPa and a Young's modulus of ca. 3.53 GPa. The toughness is even higher than that of the toughest spider silk (ca. 354 MJ m −3 ) ever found in the world, while the material also exhibits a superior tensile strength over most engineering plastics. This material is fabricated by topological confinement of the biodegradable linear polymer of poly(vinyl alcohol) (PVA) via the naturally occurring dendritic molecules of tannic acid (TA) based on high-density hydrogen bonds. Simply blending TA and PVA in aqueous solutions at acidic conditions leads to the formation of TA−PVA complexes as precipitates, which can be processed into dry TA−PVA composite products with desired shapes via the compression molding method. Compared to the conventional solution casting method for the fabrication of PVA-based thin films, the as-developed strategy allows large-scale production of bulk TA−PVA composites. The TA−PVA composites consist of interpenetrating three-dimensional supramolecular TA−PVA clusters. Such a structural feature, revealed by computational simulations, is crucial for the integrated superhigh strength and ultrahigh toughness of the material. The biodegradable TA−PVA composites are remalleable for multiple generations of recycling and healable after break, at room temperature, by the assistance of water to activate the reversibility of the hydrogen bonds. The TA−PVA composites show high promise as sustainable substitutes for conventional plastics because of their remalleability, healability, and biodegradability. The integrated superhigh strength and ultrahigh toughness of the TA−PVA composites ensure their high reliability and broad applicability.