Ni-based metal organic frameworks (Ni-MOFs) with unique hierarchical hollow ball-in-ball nanostructure were synthesized by solvothermal reactions. After successive carbonization and oxidation treatments, hierarchical NiO/Ni nanocrystals covered with a graphene shell were obtained with the hollow ball-in-ball nanostructure intact. The resulting materials exhibited superior performance as the anode in lithium ion batteries (LIBs): they provide high reversible specific capacity (1144 mAh/g), excellent cyclability (nearly no capacity loss after 1000 cycles) and rate performance (805 mAh/g at 15 A/g). In addition, the hierarchical NiO/Ni/Graphene composites demonstrated promising performance as anode materials for sodium-ion batteries (SIBs). Such a superior lithium and sodium storage performance is derived from the well-designed hierarchical hollow ball-in-ball structure of NiO/Ni/Graphene composites, which not only mitigates the volume expansion of NiO during the cycles but also provides a continuous highly conductive graphene matrix to facilitate the fast charge transfer and form a stable SEI layer.

Cell adhesion is a basic requirement for anchorage-dependent cells to survive on the matrix. It is the first step in a series of cell activities, such as cell diffusion, migration, proliferation, and differentiation. In vivo, cells are surrounded by extracellular matrix (ECM), whose physical and biochemical properties and micromorphology may affect and regulate the function and behavior of cells, causing cell reactions. Cell adhesion is also the basis of communication between cells and the external environment and plays an important role in tissue development. Therefore, the significance of studying cell adhesion in vitro has become increasingly prominent. For instance, in the field of tissue engineering and regenerative medicine, researchers have used artificial surfaces of different materials to simulate the properties of natural ECM, aiming to regulate the behavior of cell adhesion. Understanding the factors that affect cell behavior and how to control cell behavior, including cell adhesion, orientation, migration, and differentiation on artificial surfaces, is essential for materials and life sciences, such as advanced biomedical engineering and tissue engineering. This article reviews various factors affecting cell adhesion as well as the methods and materials often used in investigating cell adhesion.

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Efficiency, cost, and lifetime are the primary challenges for stationary energy storage with vanadium-redox flow and sodium-sulfur batteries as promising options. In particular, room temperature sodium-sulfur battery systems offer the potential for safe, simple, low-cost and high energy density storage, but the high reactivity or solubility of sodium polysulfides in common liquid electrolytes for carbonates or glycols, respectively, leads to rapid performance loss on cycling. Herein, we demonstrate a robust route to mostly inhibit reactivity of the sulfides with carbonate electrolytes (and also inhibit the diffusion of polysulfides

A nitrogen-doped carbonized metal–organic framework was utilized for room temperature sodium sulfur batteries. The cZIF-8/S composite electrode exhibited good cyclability over 250 cycles at 0.2C with a specific capacity of 500 mA h g−1.

The ternary phase diagrams were used to guide the design of polymer electrolyte composites. The dual-salt LiTFSI/LiBOB polymer electrolyte with optimized ionic conductivity over 1.0 mS/cm at 30 C was achieved in the isotropic phase. The lithium metal cells with free-standing polymer electrolyte exhibited outstanding average coulombic efficiency of 99.99% in the first 370 cycles, with a capacity retention of 86%.

Since the late 1980s, additive manufacturing (AM), commonly known as three-dimensional (3D) printing, has been gradually popularized. However, the microstructures fabricated using 3D printing is static. To overcome this challenge, four-dimensional (4D) printing which defined as fabricating a complex spontaneous structure that changes with time respond in an intended manner to external stimuli. 4D printing originates in 3D printing, but beyond 3D printing. Although 4D printing is mainly based on 3D printing and become an branch of additive manufacturing, the fabricated objects are no longer static and can be transformed into complex structures by changing the size, shape, property and functionality under external stimuli, which makes 3D printing alive. Herein, recent major progresses in 4D printing are reviewed, including AM technologies for 4D printing, stimulation method, materials and applications. In addition, the current challenges and future prospects of 4D printing were highlighted.

Since the publication of reports of scanning tunneling microscopy (STM) images of liquid crystals and normal alkanes on graphite,"] the generation and interpretation of STM images of organic insulating molecules adsorbed on conducting substrates have received much attention.r2] In general, the contrast variations of these images correspond to the geometrical features of the adsorbed molecules.All STM studies of normal alkanes adsorbed on graphite show that the alkane chains are aligned parallel to the graphite surface, in agreement with the conclusions drawn from earlier calorimetric studies.[31 However. it is still a matter of debate whether the orientation of the all-truns carbon skeleton of the adsorbed molecule is parallel[4. 51 or perpendicularL6] to the graphite surface. So far the question as to why insulating molecules adsorbed on a conducting surface are imaged by STM has not satisfactorily answered.In view of the increased use of STM in studying the twodimensional (2D) ordering and dynamics of the adsorbed molecules on surfaces,I6, ' I it is crucial to know the electronic origin of the STM imaging of insulating molecules adsorbed on graphite.Recently, it has been shown['] that the STM images of layered transition-metal compounds can be rationally interpreted on the basis of their partial electron density plots, p ( r o , ef),[91 calculated by the extended Huckel tight binding (EHTB) electron band structure This approach has also been successful for the interpretation of the STM images of several 2: 1 salts of the organic donor molecule bis(et1iylenedi thi0)tetrathiafulvalene (BEDT -TTF ), i .e., (BEDT-TTF),X.["] These salts possess a layered structure in which layers of donor cations BEDT-TTFo.5Q alternate with layers of the Xo anions, so that the flat surfaces of the crystal samples can be either the anion or the cation layer. For metallic salts of BEDT-TTF, the anion layer is insulating, and the cation layer is metallic. ['21 By analogy with the case of a monolayer of organic molecules (insulating) adsorbed on a semimetallic graphite sur-