Three‐dimensional carbon nanotube/graphene sandwich structures with CNT pillars grown in between the graphene layers have been developed by chemical vapor deposition. The special structure endows the high‐rate transportation of electrolyte ions and electrons throughout the electrode matrix, resulting in excellent electrochemical performance of this hybrid material.

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Lithium-sulfur batteries attract great attention due to their high energy density, while their real applications are still hindered by the rapid capacity degradation. Despite great efforts devoted to solving the polysulfide shuttle between the cathode and anode electrodes, it remains a serious challenge to build highly-stable lithium-sulfur batteries. Herein we demonstrate a strategy of introducing an ion selective membrane to improve the stability and coulombic efficiency of lithium-sulfur batteries. The sulfonate-ended perfluoroalkyl ether groups on the ionic separators are connected by pores or channels that are around several nanometers in size. These SO 3 À groups-coated channels allow ion hopping of positively charged species (Li + ) but reject hopping of negative ions, such as polysulfide anions (S n 2À) in this specific case due to the coulombic interactions. Consequently, this cation permselective membrane acts as an electrostatic shield for polysulfide anions, and confines the polysulfides on the cathode side. An ultralow decay rate of 0.08% per cycle is achieved within the initial 500 cycles for the membrane developed in this work, which is less than half that of the routine membranes. Such an ion selective membrane is versatile for various electrodes and working conditions, which is promising for the construction of high performance batteries. Broader contextThe development of high-energy-density battery systems is highly attractive to meet the growing requirement of personal devices and electric vehicles. Lithium ion batteries dominate the current market of rechargeable high energy batteries in personal electronics, while further improving the energy density requires a different energy storage mechanism. Similarly, the energy density of batteries have to be developed to make electric vehicles competitive in the market. Lithiumsulfur battery systems hold the promise of becoming the next generation of batteries due to their high energy density (2600 W h kg À1 based on the lithium-sulfur electrochemical pair). However, the special shuttle effect in lithium-sulfur batteries reduce their stability and hinder the practical application of these batteries.Here we show the proof of concept for an ion selective membrane to block the diffusion of polysulde anions across the membrane to the anode side, which greatly suppresses the so called "shuttle effect" in the lithium sulfur battery. By this method, an ultralow capacity degradation rate of 0.08 % per cycle is achieved within the rst 500 galvanostatic charge-discharge cycles.

The innovation on the low dimensional nanomaterials brings the rapid growth of nano community. Developing the controllable production and commercial applications of nanomaterials for sustainable society is highly concerned. Herein, carbon nanotubes (CNTs) with sp(2) carbon bonding, excellent mechanical, electrical, thermal, as well as transport properties are selected as model nanomaterials to demonstrate the road of nanomaterials towards industry. The engineering principles of the mass production and recent progress in the area of CNT purification and dispersion are described, as well as its bulk application for nanocomposites and energy storage. The environmental, health, and safety considerations of CNTs, and recent progress in CNT commercialization are also included. With the effort from the CNT industry during the past 10 years, the price of multi-walled CNTs have decreased from 45 000 to 100 $ kg(-1) and the productivity increased to several hundred tons per year for commercial applications in Li ion battery and nanocomposites. When the prices of CNTs decrease to 10 $ kg(-1) , their applications as composites and conductive fillers at a million ton scale can be anticipated, replacing conventional carbon black fillers. Compared with traditional bulk chemicals, the controllable synthesis and applications of CNTs on a million ton scale are still far from being achieved due to the challenges in production, purification, dispersion, and commercial application. The basic knowledge of growth mechanisms, efficient and controllable routes for CNT production, the environmental and safety issues, and the commercialization models are still inadequate. The gap between the basic scientific research and industrial development should be bridged by multidisciplinary research for the rapid growth of CNT nano-industry.

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