Two dimensional nanoarchitectures are of great interest in lithium storage for energy‐storage devices, in particular lithium‐ion batteries, due to its shortened paths for fast lithium ion diffusion and large exposed surface offering more lithium‐insertion channels. Their competitive lithium‐storage features provide huge potentials to develop next‐generation high‐performance lithium‐ion batteries. This review is devoted to the recent progress in the fabrication of innovative 2D structures with various synthetic strategies and their applications for lithium storage in lithium‐ion batteries. These 2D architectures are categorized into six styles, i.e., nanoporous nanosheets, ultrathin nanosheets, flower‐like structures assembled by nanosheets, sandwich‐like nanosheets, corrugated nanosheets, and nanosheets with specific facets. Based on the lithium‐storage manner, we further summerized their electrochemical performance for lithium storage with four classified themes including surface Li storage, zero or low‐strain Li storage, volume‐variation Li storage and synergic‐effect Li storage. Finally, the outlook and perspective on 2D lithium‐storage materials is concisely provided.

Nanomaterials in architecture for green energy conversion and/ or storage provide one of the most desirable approaches to alleviate environmental and energy issues. [1][2][3][4] As a result, there is increasing interest in developing high-power anode materials, which can match with the state-of-the-art high-power cathode materials, for next generation high-performance rechargeable Li-ion batteries. [5][6][7] Titanium dioxide is regarded as one of the ideal candidates for high-rate anode materials, owing not only to its structural characteristics and special surface activity, [8][9][10][11] but also to its low cost, safety, and environmental benignity. The lack of open channels in bulk TiO 2 is the main drawback that restricts its capacity and rate capability for reversible lithium insertion and extraction. A reduction in the effective size and construction of open channels in the material are the main strategies currently employed to increase the rate performance. [ 1 , 4 ] The capacity could also be improved by reducing the path length of lithium ion migration and improving electron transport at the surface or in the bulk of the material. [ 10 , 12,13 ] With these strategies, the capacity of ultrafi ne TiO 2 nanocrystals and nanotubes, for example, is signifi cantly enhanced at lower rates. However, their capacity and cycle life deteriorate dramatically at higher rates. [ 9 , 14-17 ] In this respect, signifi cant efforts have recently been made on the fabrication of anatase TiO 2 nanosheets with exposed highly reactive (001) facets. [ 18 -21 ] These TiO 2 nanosheets are shown to be an excellent host structure for lithium insertion and extraction due to the presence of exposed (001) facets and short path along the [001] direction for lithium ion diffusion.Although the anatase framework undergoes insignifi cant structural distortion during lithium insertion and extraction, [ 22 ] the rate of lithium diffusion is still limited by the narrow space of the host Ti-O lattice. Also, strongly caustic NaOH and corrosive HCl or HF are commonly used for the synthesis of TiO 2 nanomaterials. [ 17,18 ] Beyond these, there is still potential danger in the high-temperature and high-pressure process in low boiling point infl ammable solvents. [ 21 ] Therefore, it is highly desirable but challenging to synthesize novel TiO 2 nanostructures as high-rate anode materials through a facile and green route. As an important group of solvents, ionic liquids (ILs), which exhibit unique properties including low volatility, a wide liquid temperature range, good dissolving ability, and designability, have been intensively used in organic synthesis, catalysis, and inorganic nanomaterials synthesis. [23][24][25][26] This inspires us to design a facile ILs-based synthetic system to prepare an attractive framework for high-effi ciency lithium storage.One such framework of TiO 2 active materials is ultrathin 2D nanosheets, which allow ultrafast surface lithium storage due to maximized Li + ion diffusion and electron transport and the elimin...

CeO(2) nanoparticles/graphene nanocomposite is fabricated by depositing CeO(2) nanoparticles onto three-dimensional graphene material and its supercapacitor performance is further investigated. The nanocomposite shows a high specific capacitance and power density, demonstrating a strong synergistic effect possibly contributed from improved conductivity of CeO(2) and better utilization of graphene.

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The fluorinated surfactant N‐ethyl perfluorooctylsulfonamide can form reverse micelles with an ionic liquid as the inner component in supercritical CO2. These reverse micelles can solubilize salts and gold nanoparticles can be formed with HAuCl4 (see TEM image). The micellar systems may combine some of the advantages of supercritical CO2 and ionic liquids as solvents with benefits for potential applications.

Two conjugated microporous polymers containing thiophene-moieties (SCMPs) were obtained by the polymerization of 3,3',5,5'-tetrabromo-2,2'-bithiophene and ethynylbenzene monomers through the palladium-catalyzed Sonogashira-Hagihara crosscoupling reaction. The resulting SCMPs show high thermal stability with a decomposition temperature above 300 °C. Scanning electron microscopy images show that the resulting SCMPs formed as an aggregation composed of micrometer-sized SCMP spheres, in which honeycomb-like porous spheres with penetrated pores on the surface were observed. Taking advantage of such a unique honeycomb-like porous morphology as well as π-conjugated structures, the SCMPs show ultrahigh absorption performance for iodine vapour with an uptake of up to 345 wt% obtained, which is the highest value reported to date for CMPs, thus making the resulting SCMPs ideal absorbent materials for reversible iodine capture to address environmental issues.

Since the turn of the new century, the increasing demand for high-performance energy storage systems has generated considerable interest in rechargeable ion batteries.

The loss of sulfur in the cathode of a lithium sulfur battery (LSB) severely hinders the practical application of LSBs, and so do the insulativity of S and its lithiation end products. The incorporation of MXene can significantly improve the performance of LSBs; however, the underlying mechanism at the atomic scale has not been deeply explored. In the present work, by using density functional theory calculations, we systemically studied the interactions of lithium (poly)­sulfides (Li2S m ) on Ti-based bare MXenes (Ti n X n–1) and surface functionalized Ti2C with −F, −O, and −OH groups. Through analyzing the geometric and electronic structures, binding energies, and deformation charge densities of Li2S m adsorbed MXenes, we found that the strong Ti–S bonds dominate the interactions between Li2S m and MXenes. The strong Coulombic interactions help cathodes to confine S from dissolution. Besides, the conductivities of MXenes and Li2S m @MXenes are beneficial for the overall performance of the LSB. These will provide in-depth theoretical guidance support for the utilization of MXene in LSBs.