Garnet-type solid-state electrolytes (SSEs) are considered to be a good choice for solid-state batteries, yet the interfacial issues with metallic Li limit their applications. Herein, we propose an ultrasimple and effective strategy to enhance the interfacial connection between garnet SSEs and Li metal just by drawing a graphite-based soft interface with a pencil. Both experimental analysis and theoretical calculations confirm that the reaction between the graphite-based interfacial layer and metallic lithium forms a lithiated connection interface with good lithium-ionic and electronic conductivity. Compared to the reported interfacial materials, the graphite provides a soft interface with better ductility and compressibility. With improvement by this soft interface, the impedance of symmetric Li cells significantly decreases and the cell cycle is stable for over 1000 h. Moreover, a solid-state battery with Li-metal anode, ternary NCM523 cathode, and treated-garnet SSEs is fabricated and displays excellent rate capability and long cycling performance.

Graphene-wrapped MnO(2) nanocomposites were first fabricated by coassembly between honeycomb MnO(2) nanospheres and graphene sheets via electrostatic interaction. The materials were characterized by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, and thermogravimetric analysis. The novel MnO(2)/graphene hybrid materials were used for investigation of electrochemical capacitive behaviors. The hybrid materials displayed enhanced capacitive performance (210 F/g at 0.5 A/g). Additionally, over 82.4% of the initial capacitance was retained after repeating the cyclic voltammetry test for 1000 cycles. The improved electrochemical performance might be attributed to the combination of the pesudocapacitance of MnO(2) nanospheres with the honeycomb-like "opened" structure and good electrical conductivity of graphene sheets.

The electrochemo‐mechanical effects on the structural integrity of electrode materials during cycling is a non‐negligible factor that affects the cyclability and rate performance of all solid‐state batteries (ASSBs). Herein, combined with in situ electrochemical impedance spectroscopy (EIS), focused ion beam (FIB)–scanning electron microscope (SEM), and solid state nuclear magnetic resonance (ssNMR) techniques, the electrochemical performance and electrochemo‐mechanical behavior are compared of conventional polycrystalline NCM811 (LiNi0.8Co0.1Mn0.1O2), small‐size polycrystalline NCM811 and single‐crystal (S‐) NCM811 in Li10SnP2S12 based ASSBs during long charge–discharge cycles. The results show that the deteriorating performance of both large and small polycrystalline NCM811 originates from their inherent structural instability at >4.15 V, induced by the visible voids between the randomly oriented grains and microcracks due to the electrode pressing process and severe anisotropic volume change during cycling, rather than lithium ion transport in the primary particle. In contrast, S‐NCM811 with good microstructural integrity show remarkably high capacity (187 mAh g−1, 18 mA g−1), stable cyclability (100 cycles, retention of 64.5%), and exceptional rate capability (102 mAh g−1 at 180 mA g−1) in ASSBs even without surface modification. Moreover, 1 wt% LiNbO3@S‐NCM811 further demonstrates excellent initial discharge capacity and capacity retention. This work highlights the critical role of electrochemo‐mechanical integrity and offers an promising path towards mechanically‐reliable cathode materials for ASSBs.

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Slow lithium diffusion kinetics of H1 phase during discharge determines the initial irreversible capacity loss of NCM-based materials. By controlling lithium diffusion rate in the discharge process, extra capacity is obtained in the materials.

High-performance broadband photodetectors have recently attracted signifi cant interest [1][2][3][4][5] because of their importance to a variety of applications, including imaging, remote sensing, environmental monitoring, astronomical detection, photometers and analytical applications. Graphene is a promising material for broadband photodetection applications because of its ability to absorb incident light over a wide wavelength range, from at least the visible (VIS) spectrum to the infrared. [ 6 ] Recent works have demonstrated that zerobandgap single-or few-layer graphene-based photodetectors based on a fi eld-effect transistor (FET) structure could operate in the near-infrared (NIR) and VIS parts of the electromagnetic spectrum. [ 7,8 ] However, no working spectra have been demonstrated for these zero-bandgap graphene photodetectors in longer wavelength ranges. Theoretical calculations indicated that opening and varying the bandgap of

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