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Silicon (Si) is one of the most promising materials for the next-generation anode of lithium-ion batteries (LIBs). It not only has the highest theoretical capacity but also is rich in natural resources and related mature technologies. However, its large volume fluctuation and poor electrical conduction must be overcome by compositing it with guest materials. Different from complicated methods that run counter to industrialized applications, herein, a facile and efficient strategy has been applied to prepare an editable Si composite precursor within 30 seconds with rapid biomineralization. After simple post-processing, a high-performance carbon-coated Si composite electrode was obtained, which exhibited good electrical contact, structural stability, and favorable diffusion paths and space for electrolytes. Specifically, this biomineralization strategy improves the capability of lithium storage in the Si electrode with a high-reversible specific capacity. The electrode shows an excellent rate capability at large current density (4 A g−1) and excellent capacity retention in long-term cycling (600 cycles). This approach also provides a new choice to synthesize rapidly diverse electrodes for high-performance lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Silicon‐based materials have shown great potential and been widely studied in various fields. Unlike its unparalleled theoretical capacity as anodes for batteries, few investigations have been reported on silicon‐based materials for applications in supercapacitors. Here, an electrode composed of layered silicon‐based nanosheets, obtained through oxidation and exfoliation, for a supercapacitor operated up to 4 V is reported. These silicon‐based nanosheets show an areal specific capacitance of 4.43 mF cm−2 at 10 mV s−1 while still retaining a specific capacitance of 834 µF cm−2 even at an ultrahigh scan rate of 50 000 mV s−1. The volumetric energy and power density of the supercapacitor are 7.65 mWh cm−3 and 9312 mW cm−3, respectively, and the electrode can operate for 12000 cycles in a potential window of 4 V at 2 A g−1, while retaining 90.6% capacitance. These results indicate that the silicon‐based nanosheets can be a competitive candidate as the supercapacitor electrode material. [ABSTRACT FROM AUTHOR]

The development of inorganic functionalized membranes with the capacity to effectively separate molecules or ions in solutions based on the size or electrostatic interactions is pivotal to purification and separation applications. Herein, we demonstrate a novel green strategy utilizing a completely aqueous process to construct an asymmetrically structured metal surface functionalized polymer–matrix nanocomposite nanofiltration membrane. Crosslinked polyethyleneimine (PEI) is grafted on a carboxylated carbon nanotube intermediate layer incorporated into the macroporous cellulose acetate substrate to form the composite membrane. The resulting membrane is subsequently inorganically modified via an in situ surface reaction of zinc nitrate with excess ammonium hydroxide to produce the hydrophilic and positively charged membrane. Crosslinking enhances the polymer interaction with the carbon nanotube interlayer which in turn endows it with mechanical strength and sustains the membrane pore structure during pressure driven filtration. The functionalized membrane displays outstanding pure water flux of 16.5 ± 1.3 L m−2 h−1 bar−1 while exhibiting good nanofiltration performance of bivalent cations, which is ascribed to the electrostatic repulsion via the Donnan exclusion effect. Meanwhile the membranes exhibit excellent separation of organic molecules and long-term filtration stability. This newly developed approach presents a promising route for the construction of highly permeable nanofiltration membranes for fast purification and separation applications. [ABSTRACT FROM AUTHOR]