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The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/smll.201905296. Omnibearing acceleration of charge/ion transfer in Li 4 Ti 5 O 12 (LTO) electrodes is of great significance to achieve advanced high-rate anodes in lithium-ion batteries. Here, a synergistic combination of hydrogenated LTO nanoparticles (H-LTO) and N-doped carbon fibers (NCFs) prepared by an electrodepositionatomic layer deposition method is reported. Binder-free conductive NCFs skeletons are used as strong support for H-LTO, in which Ti 3+ is self-doped along with oxygen vacancies in LTO lattice to realize enhanced intrinsic conductivity. Positive advantages including large surface area, boosted conductivity, and structural stability are obtained in the designed H-LTO@NCF electrode, which is demonstrated with preeminent high-rate capability (128 mAh g −1 at 50 C) and long cycling life up to 10 000 cycles. The full battery assembled by H-LTO@NCFs anode and LiFePO 4 cathode also exhibits outstanding electrochemical performance revealing an encouraging application prospect. This work further demonstrates the effectiveness of self-doping of metal ions on reinforcing the high-rate charge/discharge capability of batteries. www.advancedsciencenews.com

Lithium ion batteries (LIBs) have gradually conquered the market of modern electronic equipment and electric vehicles for decades. [1][2][3][4] However, currently, common LIBs are still faced with great challenges, because commercial graphite anode cannot meet the growing demand for high capacity. [5][6][7] Therefore, it is urgent to explore and design advanced highcapacity electrode materials.Transition metal sulfides such as nickel sulfides (NiS, Ni 3 S 2 , Ni 3 S 4 , etc.) [8][9][10][11] have been extensively reported as electrode materials due to their excellent chemical stability and high theoretical capacity. [9,12] Among them, Ni 3 S 2 is considered as one of the most promising electrodes for energy storage due In this work, a facile strategy for the construction of single crystalline Ni 3 S 2 nanowires coated with N-doped carbon shell (NC) forming Ni 3 S 2 @NC core/ shell arrays by one-step chemical vapor deposition process is reported. In addition to the good electronic conductivity from the NC shell, the nanowire structure also ensures the accommodation of large volume expansion during cycling, leading to pre-eminent high-rate capacities (470 mAh g −1 at 0.05 A g −1 and 385 mAh g −1 at 2 A g −1 ) and outstanding cycling stability with a capacity retention of 91% after 100 cycles at 1 A g −1 . Furthermore, ex situ transmission electron microscopy combined with X-ray diffraction and Raman spectra are used to investigate the reaction mechanism of Ni 3 S 2 @NC during the charge/ discharge process. The product after delithiation consists of Ni 3 S 2 and sulfur, suggesting that the capacity of the electrode comes from the conversion reaction of both Ni 3 S 2 and sulfur with Li 2 S.

The curved surfaces conformality has become the coming barrier to the implementation of the metasurface carpet cloaks. A curved conformal strategy that can balance the electromagnetic performances and the manufacturing challenges of metasurface simultaneously is highly in demand, but yet underexplored. Herein, a novel thermal programming 3D‐printing method for curved conformal metasurface is proposed. Owing to the glass‐rubber transition characteristics of thermoplastic polymers, the advantages of rigid substrate and flexible substrate are fully utilized to achieve the conformality of metasurface, which ingeniously reduces the manufacturing complexity and ensures the electromagnetic performances. As a proof, an arched metasurface carpet cloak composed of the easy‐bending unit cells is designed and fabricated by the composite fused deposition molding of polylactic acid and Sn‐Bi materials with the thermal programming process. Experiments prove that the maximum reduced total radar cross section of the conformal cloak reaches about −9.4 dB while the 3 dB reduction bandwidth is ≈26.6%. The excellent cloaking performance of the metasurface sample demonstrates the effectiveness of this curved conformal method. This work provides a viable implementation strategy for complex curved metasurface and will substantially promote the applications of the conformal invisibility cloaks.

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