There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

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.

Metal Organic Frameworks Derived Hierarchical Hollow NiO/Ni/Graphene Composites for Lithium and Sodium Storage

Diverse Metal–Organic Framework Architectures for Electromagnetic Absorbers and Shielding

Hydrogen produced via water electrolysis can act as an ideal clean chemical fuel with superb gravimetric energy density and high energy conversion efficiency, solving the problems of conventional fossil fuel exhaustion and environmental contamination. Transition metal sulfides (TMS) have been extensively explored as effective, widely available alternatives to precious metals in overall water splitting. Herein, recent advances, covering preparation methods, intrinsic electrocatalytic performance, and optimization strategies, relating to TMS-based bifunctional electrocatalysts have been summarized systematically and comprehensively. Firstly, a general introduction to the reaction mechanisms and key parameters of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is provided. Next, the physicochemical properties of TMS and typical synthesis methods are introduced to give guidance for fabricating TMS materials with well-defined structures, controllable compositions, and excellent performance. Importantly, the intrinsic activities of TMS-based electrocatalysts and several strategies for improving their bifunctional electrocatalytic performance during water electrolysis are discussed in detail. Finally, perspectives covering the challenges and opportunities related to the further development of TMS-based materials with high activity and long-term durability for overall water splitting are given. The aim herein is to provide guidelines for the design and fabrication of TMS-based bifunctional electrocatalysts with excellent performance and to accelerate their large-scale practical application in water electrolysis.

Recent advances in transition-metal-sulfide-based bifunctional electrocatalysts for overall water splitting

A review on carbon/magnetic metal composites for microwave absorption

In this paper, interlaminar failure behavior of GLARE-3/2-0.3 laminates under short-beam three-point-bending load were investigated with various span length-to-specimen thickness ratios (L/h). Failure modes and damage characteristics at different loading stages were observed by Scanning Electron Microscopy (SEM) to assess the failure behavior. It was found that failure modes changed accordingly with varying L/h ratios. A valid shear dominant failure mode was obtained at the L/h ratio of 8. Moreover, there were significant differences in failure modes and damage characteristics among three GLARE variants. The results also showed that lay-up configuration of glass/epoxy layer strongly affected load-deflection response, especially the failure load, and corresponding failure mode.

Interlaminar failure behavior of GLARE laminates under short-beam three-point-bending load

A novel Fibre–Metal Laminates (FMLs) based on carbon fibre reinforced PMR polyimide were prepared using a hot press process in this paper. Pre-treatment on the titanium surface were conducted prior to laminating. Scanning Electron Microscope (SEM) were used to observe the morphologies of the titanium and the cross-sections of the FMLs. SEM results showed that micro-roughness structures were formed on the titanium surface after anodization. This structure enhanced the interlaminar bond strength between titanium and polyimide. Flexural and Interlaminar shear (ILSS) tests showed that the FMLs possess excellent flexural and interlaminar properties at both room temperature and elevated temperature. Thermostability tests proved that the FMLs based on carbon fibre reinforced PMR polyimide offered excellent thermal properties. It is shown that no delamination appears between titanium layer and the fibre-reinforced polyimide layer after 1000 times thermal shock.

Preparation and properties of Fibre-Metal Laminates based on carbon fibre reinforced PMR polyimide

This paper studied a thermoplastic-based fiber metal laminate (FML) prepared via a hot-pressing process utilizing titanium foils, carbon fiber reinforced PEEK prepregs, and PEEK films (interface bonding layers). The open-hole tensile progressive damage and failure mechanisms were investigated by numerical and experimental methods. During the simulation, we employed three failure criterions for titanium (ductile damage), prepregs (a progressive damage in terms of strains), and interface bonding layers (cohesive model) to predict the failure of the laminates. In the experiments, the damage behavior was further verified. The open-hole tensile strength and stress–strain response agreed well with the numerical results. It was found that fiber breakage along the loading direction initiated after yield point of the laminates, following by matrix damage. When the applied load reached the ultimate value, the delamination between the titanium layer and the fiber layer propagated to the entire section, causing titanium fracture. The validated model can also be used on other notched or bolted FMLs with similar structure.

Open-hole tensile progressive damage and failure prediction of carbon fiber-reinforced PEEK–titanium laminates

With the increase of oil spill accidents and discharge of oily wastewater, a novel oil adsorption material with superhydrophobicity and reusability is desired. To our knowledge, low surface energy ...

Yubing Hu

Papers

Interlaminar failure behavior of GLARE laminates under short-beam three-point-bending load

Preparation and properties of Fibre-Metal Laminates based on carbon fibre reinforced PMR polyimide

Open-hole tensile progressive damage and failure prediction of carbon fiber-reinforced PEEK–titanium laminates

Design of Recyclable Superhydrophobic PU@Fe3O4@PS Sponge for Removing Oily Contaminants from Water

Effect of adhesive quantity on failure behavior and mechanical properties of fiber metal laminates based on the aluminum–lithium alloy