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Silicon is an attractive anode material in energy storage devices, as it has a ten times higher theoretical capacity than its state-of-art carbonaceous counterpart. However, the common process to synthesize silicon nanostructured electrodes is complex, costly, and energy-intensive. Three-dimensional (3D) porous silicon-based anode materials have been fabricated from natural reed leaves by calcination and magnesiothermic reduction. This sustainable and highly abundant silica source allows for facile production of 3D porous silicon with very good electrochemical performance. The obtained silicon anode retains the 3D hierarchical architecture of the reed leaf. Impurity leaching and gas release during the fabrication process leads to an interconnected porosity and the reductive treatment to an inside carbon coating. Such anodes show a remarkable Li-ion storage performance: even after 4000 cycles and at a rate of 10 C, a specific capacity of 420 mA h g(-1) is achieved.

The preparation and electrochemical storage behavior of MoS 2 nanodots-more precisely single-layered ultrasmall nanoplates-embedded in carbon nanowires has been studied. The preparation is achieved by an electrospinning process that can be easily scaled up. The rate performance and cycling stability of both lithium and sodium storage were found to be outstanding. The storage behavior is, moreover, highly exciting from a fundamental point of view, as the differences between the usual storage modes-insertion, conversion, interfacial storage-are beneficially blurred. The restriction to ultrasmall reaction domains allows for an almost diffusionless and nucleation-free "conversion", thereby resulting in a high capacity and a remarkable cycling performance.

oxidation, [3] the oxygen reduction reaction, [4] hydrogen oxidation reaction, [5] and hydrogen evolution reaction (HER). [6] The scarcity and high cost of Pt have necessitated the development of catalytic systems with increased activity, utilization, and durability of Pt atoms. In this respect, the increase of Pt dispersion on supports by downsizing metals to the atomic scale is of significance for maximizing the Pt utilization and consequently increasing the mass activity and turnover frequency (TOF). [7,8] However, in most cases, the electronic properties of the supported Pt atoms are highly dependent on coordination/supporting environments, which have been shown to be crucial for enabling the Pt catalysts with high intrinsic activity. [9] In recent years, abundant efforts have been made to synthesize the atomic Pt catalysts with tailored coordination environments on diverse supports, such as the N/S-doped carbon materials (Pt 1 /NC, [10] PtRuC [11] ), metal oxides (PtCoO, [12] PtFe 2 O 3 [13] ), metal sulfides (PtMoS 2 [14] ), etc. Anchoring Pt atoms by neighboring strong electronegative atoms will lead to a large charge transfer from Pt to coordinated O/N/S atoms, Platinum-based catalysts occupy a pivotal position in diverse catalytic applications in hydrogen chemistry and electrochemistry, for instance, the hydrogen evolution reactions (HER). While adsorbed Pt atoms on supports often cause severe mismatching on electronic structures and HER behaviors from metallic Pt due to the different energy level distribution of electron orbitals.Here, the design of crystalline lattice-confined atomic Pt in metal carbides using the Pt-centered polyoxometalate frameworks with strong PtO-metal covalent bonds is reported. Remarkably, the lattice-confined atomic Pt in the tungsten carbides (Pt doped @WC x , both Pt and W have atomic radii of 1.3 Å) exhibit near-zero valence states and similar electronic structures as metallic Pt, thus delivering matched energy level distributions of the Pt 5d z 2 and H 1s orbitals and similar acidic hydrogen evolution behaviors. In alkaline conditions, the Pt doped @WC x exhibits 40 times greater mass activity (49.5 A mg Pt −1 at η = 150 mV) than the Pt@C because of the favorable water dissociation and H* transport. These findings offer a universal pathway to construct urgently needed atomic-scale catalysts for broad catalytic reactions.

Metal fluoride (MF) conversion cathodes theoretically show higher gravimetric and volumetric capacities than Ni-or Co-based intercalation oxide cathodes, which makes metal fluoride−lithium batteries promising candidates for nextgeneration high-energy-density batteries. However, their highenergy characteristics are clouded by low-capacity utilization, large voltage hysteresis, and poor cycling stability of transition MF cathodes. A variety of reasons is responsible for this: poor reaction kinetics, low conductivities, unstable MF/electrolyte interfaces and dissolution of active species upon cycling. Herein, we combine the synthesis of the metal−organicframework (MOF) with the low-temperature fluorination to prepare MOF-shaped CoF 2 @C nanocomposites that exhibit confinement of the CoF 2 nanoparticles and efficient mixed-conducting wiring in the produced architecture. The ultrasmall CoF 2 nanoparticles (5−20 nm on average) are uniformly covered by graphitic carbon walls and embedded in the porous carbon framework. Within the CoF 2 @C nanocomposite, the cross-linked carbon wall and interconnected nanopores serve as electron-and ion-conducting pathways, respectively, enabling a highly reversible conversion reaction of CoF 2 . As a result, the produced CoF 2 @C composite cathodes successfully restrain the above-mentioned challenges and demonstrate high-capacity utilization of ∼500 mAh g −1 at 0.2C, good rate capability (up to 2C), and long-term cycle stability over 400 cycles. Overall, the presented study not only reports on a simple composite design to achieve high-energy characteristics in CoF 2 −Li batteries but also may provide a general solution for many other metal fluoride−lithium batteries.

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Silicon is an attractive anode material in energy storage devices,asithas aten times higher theoretical capacity than its state-of-art carbonaceous counterpart. However,t he common process to synthesize silicon nanostructured electrodes is complex, costly,a nd energy-intensive.T hree-dimensional (3D) porous silicon-based anode materials have been fabricated from natural reed leaves by calcination and magnesiothermic reduction. This sustainable and highly abundant silica source allows for facile production of 3D porous silicon with very good electrochemical performance.T he obtained silicon anode retains the 3D hierarchical architecture of the reed leaf.I mpurity leaching and gas release during the fabrication process leads to an interconnected porosity and the reductive treatment to an inside carbon coating. Such anodes show ar emarkable Li-ion storage performance:e ven after 4000 cycles and at ar ate of 10 C, as pecific capacity of 420 mA hg À1 is achieved.

Electrocatalysts In article number 2206368, Yi Wang, Li Qiu, Yang‐Gang Wang, Chong Cheng, and co‐workers report on engineering crystalline‐lattice‐confined atomic Pt in metal carbides, which exhibits near‐zero valence states, similar electronic structures, and matched hydrogen evolution behaviors as the Pt(111) surface. Remarkably, the Pt‐doped@WCx catalyst delivers 40 times greater mass activity than Pt@C‐20% in alkaline conditions.