High specific capacity battery electrode materials have attracted great research attention. Phosphorus as a low-cost abundant material has a high theoretical specific capacity of 2596 mAh/g with most of its capacity at the discharge potential range of 0.4-1.2 V, suitable as anodes. Although numerous research progress have shown other high capacity anodes such as Si, Ge, Sn, and SnO2, there are only a few studies on phosphorus anodes despite its high theoretical capacity. Successful applications of phosphorus anodes have been impeded by rapid capacity fading, mainly caused by large volume change (around 300%) upon lithiation and thus loss of electrical contact. Using the conducting allotrope of phosphorus, "black phosphorus" as starting materials, here we fabricated composites of black phosphorus nanoparticle-graphite by mechanochemical reaction in a high energy mechanical milling process. This process produces phosphorus-carbon bonds, which are stable during lithium insertion/extraction, maintaining excellent electrical connection between phosphorus and carbon. We demonstrated high initial discharge capacity of 2786 mAh·g(-1) at 0.2 C and an excellent cycle life of 100 cycles with 80% capacity retention. High specific discharge capacities are maintained at fast C rates (2270, 1750, 1500, and 1240 mAh·g(-1) at C/5, 1, 2, and 4.5 C, respectively).

We reported a simple synthetic method for Cu–Zn–In–S nanocrystals (NCs) using commercially available, low toxic precursors. The various sizes and composition of Cu–Zn–In–S NCs were well controlled by simply changing reaction temperature and the ratio of the precursors, respectively. Accordingly, as produced these particles exhibited tunable photoluminescence (PL) spectra with emission color tuned from visible to the NIR region and had a relatively high QY of over 70% without coating any wide band gap shell materials. Further experimental results revealed that Cu–Zn–In–S NCs showed some advantages in contrast to typical plain II–VI and III–V semiconductor NCs. Preliminary tentative application on the preparation of QD-LEDs verified the feasibility in the lighting field.

Herein we report a self-cleaning coating derived from zwitterionic poly(2-methacryloyloxylethyl phosphorylcholine) (PMPC) brushes grafted on a solid substrate. The PMPC surface not only exhibits complete oil repellency in a water-wetted state (i.e., underwater superoleophobicity), but also allows effective cleaning of oil fouled on dry surfaces by water alone. The PMPC surface was compared with typical underwater superoleophobic surfaces realized with the aid of surface roughening by applying hydrophilic nanostructures and those realized by applying smooth hydrophilic polyelectrolyte multilayers. We show that underwater superoleophobicity of a surface is not sufficient to enable water to clean up oil fouling on a dry surface, because the latter circumstance demands the surface to be able to strongly bond water not only in its pristine state but also in an oil-wetted state. The PMPC surface is unique with its described self-cleaning performance because the zwitterionic phosphorylcholine groups exhibit exceptional binding affinity to water even when they are already wetted by oil. Further, we show that applying this PMPC coating onto steel meshes produces oil-water separation membranes that are resilient to oil contamination with simply water rinsing. Consequently, we provide an effective solution to the oil contamination issue on the oil-water separation membranes, which is an imperative challenge in this field. Thanks to the self-cleaning effect of the PMPC surface, PMPC-coated steel meshes can not only separate oil from oil-water mixtures in a water-wetted state, but also can lift oil out from oil-water mixtures even in a dry state, which is a very promising technology for practical oil-spill remediation. In contrast, we show that oil contamination on conventional hydrophilic oil-water separation membranes would permanently induce the loss of oil-water separation function, and thus they have to be always used in a completely water-wetted state, which significantly restricts their application in practice.

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Co3O4/Co2MnO4 nanocomposites, derived from a single-source CoMn-layered double hydroxide precursor, exhibit excellent bifunctional oxygen electrode activities for both oxygen reduction and evolution reactions, which can be attributed to the large specific surface area and well-dispersed heterogeneous structure of the nanocomposites.

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The mechanics problem concerning large axisymmetric deformations of nonlinear membranes is reformulated in terms of a system of three first-order ordinary differential equations with explicit derivatives. With a set of proper boundary conditions, arrangements are made to change the boundary-value problem into the form of an initial value problem such that the solution can be obtained by standard numerical methods for integrating ordinary differential equations. The system of equations derived applies to the class of all axisymmetric deformations of membranes with a general elastic stress-strain relation. Three examples are given on inflating of a flat membrane, longitudinal stretching of a tube, and flattening of a semispherical cap. In the examples, the Mooney model are assumed to describe the material behavior of the membranes. The solution on the flat membrane serves to compare with an existing one in literature. The solutions on the tube and the cap are new.

Ferroelectric ceramics are susceptible to fracture under high magnitude cyclic electric field. Flaws concentrate the electric field, inducing a large incompatible strain, and thereby a large stress. Stable growth of cracks with either conducting or insulating interiors is observed in 8/65/35 lanthanum lead zirconate titanate samples. Indentations on the electroded surface are filled with distilled water or a water-salt solution. Under cyclic electric field, tree like damage grows from the indented electrode. Indentations on the surfaces 90" to the electrodes are filled with silicone oil. This results in stable crack growth perpendicular to the cyclic electric field. Nonlinear fracture models are presented for both conducting and insulating cracks. Tensile stress intensity factors are predicted for both cases.