Constructing three-dimensional (3D) architecture with oriented configurations by two-dimensional nanobuilding blocks is highly challenging but desirable for practical applications. The well-oriented open structure can facilitate storage and efficient transport of ion, electron, and mass for high-performance energy technologies. Using MoS2 as an example, we present a facile and effective hydrothermal method to synthesize 3D radially oriented MoS2 nanospheres. The nanosheets in the MoS2 nanospheres are found to have less than five layers with an expanded (002) plane, which facilitates storage and efficient transport of ion, electron, and mass. When evaluated as anode materials for rechargeable Li-ion batteries, the MoS2 nanospheres show an outstanding performance; namely, a specific capacity as large as 1009.2 mA h g(-1) is delivered at 500 mA g(-1) even after 500 deep charge/discharge cycles. Apart from promising the lithium-ion battery anode, this 3D radially oriented MoS2 nanospheres also show high activity and stability for the hydrogen evolution reaction.

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The lithium-sulfur battery is one of the most prospective chemistries in secondary energy storage field due to its high energy density and high theoretical capacity. However, the dissolution of polysulfides in liquid electrolytes causes the shuttle effect, and the rapid decay of lithium sulfur battery has greatly hindered its practical application. Herein, combination of sulfonated reduced graphene oxide (SRGO) interlayer on the separator is adopted to suppress the shuttle effect. We speculate that this SRGO layer plays two roles: physically blocking the migration of polysulfide as ion selective layer and anchoring lithium polysulfide by the electronegative sulfonic group. Lewis acid-base theory and density functional theory (DFT) calculations indicate that sulfonic groups have a strong tendency to interact with lithium ions in the lithium polysulfide. Hence, the synergic effect involved by the sulfonic group contributes to the enhancement of the battery performance. Furthermore, the uniformly distributed sulfonic groups working as active sites which could induce the uniform distribution of sulfur, alleviating the excessive growth of sulfur and enhancing the utilization of active sulfur. With this interlayer, the prototype battery exhibits a high reversible discharge capacity of more than 1300 mAh g and good capacity retention of 802 mAh g after 250 cycles at 0.5 C rate. After 60 cycles at different rates from 0.2 to 4 C, the cell with this functional separator still recovered a high specific capacity of 1100 mAh g at 0.2 C. The results demonstrate a promising interlayer design toward high performance lithium-sulfur battery with longer cycling life, high specific capacity, and rate capability.

Two-dimensional (2D) layered transition-metal dichalcogenides (LTMDs) display various crystal phases with distinct symmetries, structures, and physical properties. Exploring and designing different structural phases in two dimensions could provide an avenue for switching material properties, aiming at practical applications for potential fields. Here we demonstrate a conceptually designed approach to narrow the band gap of MoSe and obtain a conductive red MoSe nanosheet. By introducing the high valence state of Mo species and constructing the Mo-O bonding on the surface of the MoSe nanosheets, the electronic properties can be modified and the conductivity is accordingly improved, an effect that significantly improves their lithium storage capacity and high-rate capability. We anticipate that the exploration of the conductive red MoSe with tunable band gap could help us unlock more potential crystal structures of LTMD-based and even other 2D materials for further applications.

Solid polymer electrolytes (SPEs) have shown extraordinary promise for all-solid-state lithium metal batteries with high energy density and flexibility but are mainly limited by low ionic conductivity and their poor stability with lithium metal anodes. In this work, we propose a highly ordered porous electrolyte additive derived from SSZ-13 for high-rate all-solid-state lithium metal batteries. The nanoporous adsorption effect provided by the highly ordered porous nanoparticles in the poly(ethylene oxide) (PEO) electrolyte is found to significantly improve the Li conductivity (1.91 × 10 S cm at 60 °C, 4.43 × 10 S cm at 20 °C) and widen the electrochemical stability window to 4.7 V vs Li/Li. Meanwhile, the designed PEO-based electrolyte demonstrates enhanced stability with the lithium metal anode. Through systematically increasing Li diffusion, widening the electrochemical stability window, and enhancing the interfacial stability of the SSZ-composite electrolyte (CPE) electrolyte, the LiFePO/SSZ-CPE/Li cell is optimized to deliver high rate capability and stable cycling performance, which demonstrates great potential for all-solid-state energy storage application.

The direct lattice strain, either distortion, compressive, or tensile, can efficiently alter the intrinsic electrocatalytic property of the catalysts. In this work, we report a novel and effective strategy to distort the lattice structure by constructing a metastable MoSSe solid solution and thus, tune its catalytic activity for the Li-O batteries. The lattice distortion structure with inequivalent interplanar spacing between the same crystals plane were directly observed in individual MoSSe nanosheets with transmission electron microscopy and aberration-corrected transmission electron microscopy. In addition, in situ transmission electron microscopy analysis revealed the fast Li diffusion across the whole metastable structure. As expected, when evaluated as oxygen electrode for deep-cycle Li-O batteries, the metastable MoSSe solid solution deliver a high specific capacity of ∼730 mA h g with stable discharge-charge overpotentials (0.17/0.49 V) over 30 cycles.

A covalently bonded polyethylenimine–rGO–MWCNT composite achieves outstanding performance at an ultra-high sulfur loading of up to 18 mg cm−2.

Graphene nanosheets loaded with highly dispersed platinum nanoparticles (Pt@GNSs) are prepared by a simple and effective hydrothermal method.