The abundant reserve and low cost of sodium have provoked tremendous evolution of Na-ion batteries (SIBs) in the past few years, but their performances are still limited by either the specific capacity or rate capability. Attempts to pursue high rate ability with maintained high capacity in a single electrode remains even more challenging. Here, an elaborate self-branched 2D SnS (B-SnS) nanoarray electrode is designed by a facile hot bath method for Na storage. This interesting electrode exhibits areal reversible capacity of ca. 3.7 mAh cm (900 mAh g) and rate capability of 1.6 mAh cm (400 mAh g) at 40 mA cm (10 A g). Improved extrinsic pseudocapacitive contribution is demonstrated as the origin of fast kinetics of an alloying-based SnS electrode. Sodiation dynamics analysis based on first-principles calculations, ex-situ HRTEM, in situ impedance, and in situ Raman technologies verify the S-edge effect on the fast Na migration and reversible and sensitive structure evolution during high-rate charge/discharge. The excellent alloying-based pseudocapacitance and unsaturated edge effect enabled by self-branched surface nanoengineering could be a promising strategy for promoting development of SIBs with both high capacity and high rate response.

Two porous covalent organic frameworks (COFs) with good biocompatibility were employed as drug nanocarriers, where three different drugs were loaded for subsequent drug release in vitro. The present work demonstrates that COFs are applicable in drug delivery for therapeutic applications.

Although being considered as one of the most promising cathode materials for Lithium-ion batteries (LIBs), LiNi1/3Co1/3Mn1/3O2 (NCM) is currently limited by its poor rate performance and cycle stability resulting from the thermodynamically favorable Li+/Ni2+ cation mixing which depresses the Li+ mobility. In this study, we developed a two-step method using fluffy MnO2 as template to prepare hierarchical porous nano-/microsphere NCM (PNM-NCM). Specifically, PNM-NCM microspheres achieves a high reversible specific capacity of 207.7 mAh g−1 at 0.1 C with excellent rate capability (163.6 and 148.9 mAh g−1 at 1 C and 2 C), and the reversible capacity retention can be well-maintained as high as 90.3% after 50 cycles. This excellent electrochemical performance is attributed to unique hierarchical porous nano-/microsphere structure which can increase the contact area with electrolyte, shorten Li+ diffusion path and thus improve the Li+ mobility. Moreover, as revealed by XRD Rietveld refinement analysis, a negligible cation mixing (1.9%) and high crystallinity with a well-formed layered structure also contribute to the enhanced C-rates performance and cycle stability. On the basis of our study, an effective strategy can be established to reveal the fundamental relationship between the structure/chemistry of these materials and their properties.

Two fully conjugated covalent organic frameworks present high performance for both gas capture and Li ion storage, confirming their high potential in future Li–gas battery applications.

Sensory memory is capable of recording information and giving feedback based on external stimuli. Haptic memory in particular can retain the sensation of the interaction between the human body and the environment and help humans to describe the physical quantities in their environment and manipulate objects in daily activities. Although sensitive and accurate tactile sensors have been produced on optical and electronic devices, their rigorous operation and equipment requirements seriously limit their further applicability. In addition, their poor retainability after the removal of external stimuli also warrants further improvements. Thus, haptic memory materials, having simple structures and high sensitivity, are highly desired. Herein, we successfully developed two piezochromic assemblies assisted by halogen bonding for haptic memory. The halogen bond not only contributes to the fabrication of the network and enhances integrative stability but also broadens the natural piezofluorescent range, thus promoting sensory sensitivity. Moreover, the colorimetric change of the assemblies could be well-retained after the stimulus was removed. Upon mild heating treatment, the piezochromic response could be recovered to its original state, confirming the recyclability of this haptic memory material for use in practical applications. The present work enriches the library of piezochromic materials with enhanced performance for haptic memory.

The adaptive property of supramolecular building blocks facilitates noncovalent synthesis of soft materials. While it is still a challenging task, fine-tuning and precise control over topological nanostructures constructed from the self-assembly of low-molecular-weight building blocks are an important research direction to investigate the structure–property relationship. Herein, we report controlled self-assembly evolution of a low-molecular-weight building block bearing cholesterol and naphthalene-dicarboximide moieties, showing ultrasensitivity to solvent polarity. In low-polarity solvents (<4), it could form an M-type fiber-constituted organogel (supergel) with high solvent content, columnar molecular packing, and self-healing property. Highly polar solvents (>7.8) favor the formation of P-type helical nanostructures terminated by nanotoroids, having lamellar molecular packing. With a further increase in solvent polarity (up to 9.6), unilamellar and multilamellar vesicles were generated, which could undergo an aggregation-induced fusion process to form branched nanotubes tuned by the concentration. Self-attractive interactions between aggregates were found to be responsible for the formation of superstructures including helix–nanotoroid junctions as well as membrane-fused nanotubes.

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Herein we have developed a highly active, robust, and selective porous organic polymer (PPTPA-1, POP) encapsulated magnetically retrievable Pd-Fe 3 O 4 nanohybrid catalyst in a one-step solvothermal route and investigated its catalytic performance in levulinic acid (LA) hydrogenation, a key platform molecule in many biorefinery schemes, to γ-valerolactone (GVL), employing formic acid as sustainable H 2 source. The specific textural and chemical characteristics of as-synthesized nanohybrid materials were identified by XRD, XPS, FT-IR, 13 C CP MAS NMR, HR-TEM, and FE-SEM with the corresponding elemental mapping and nitrogen physisorption studies. It was found that the nanohybrid Pd-Fe 3 O 4 /PPTPA-1 catalyst exhibited a substantially enhanced activity in comparison with the monometallic catalysts (Pd/PPTPA-1 and Fe 3 O 4 /PPTPA-1). Evidence of the electronic interaction between Pd and Fe attributable to the intrinsic hybrid synergistic effect is thought to be responsible for this superior catalytic performance and improvement in catalyst stability. The recycling experiments revealed that the magnetic nanohybrid catalyst sustained remarkable recycling efficiency and magnetism after being used in 10 successive catalytic runs, which made Pd-Fe 3 O 4 /PPTPA-1 a potential catalyst for the production of GVL in industry.