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To address the volume-change-induced pulverization problems of electrode materials, we propose a "silica reinforcement" concept, following which silica-reinforced carbon nanofibers with encapsulated Sb nanoparticles (denoted as SiO/Sb@CNFs) are fabricated via an electrospinning method. In this composite structure, insulating silica fillers not only reinforce the overall structure but also contribute to additional lithium storage capacity; encapsulation of Sb nanoparticles into the carbon-silica matrices efficiently buffers the volume changes during Li-Sb alloying-dealloying processes upon cycling and alleviates the mechanical stress; the porous carbon nanofiber framework allows for fast charge transfer and electrolyte diffusion. These advantageous characteristics synergistically contribute to the superior lithium storage performance of SiO/Sb@CNF electrodes, which demonstrate excellent cycling stability and rate capability, delivering reversible discharge capacities of 700 mA h/g at 200 mA/g, 572 mA h/g at 500 mA/g, and 468 mA h/g at 1000 mA/g each after 400 cycles. Ex situ as well as in situ TEM measurements confirm that the structural integrity of silica-reinforced Sb@CNF electrodes can efficiently withstand the mechanical stress induced by the volume changes. Notably, the SiO/Sb@CNF//LiCoO full cell delivers high reversible capacities of ∼400 mA h/g after 800 cycles at 500 mA/g and ∼336 mA h/g after 500 cycles at 1000 mA/g.

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Metal-doped zeolitic imidazolate framework-8 (ZIF-8)-derived carbon materials are attractive for the electrocatalytic reduction of CO2 into CO. In such carbon materials, due to the fusion and aggregation of ZIF-8 precursors during the high-temperature pyrolysis process, it is desirable yet still challenging to create a high specific surface area with more active sites available for reacting with reactants. Using SiO2 as a protective coating on the ZIF-8 surface, we synthesize Fe, N-co-doped porous carbon nanoparticles (Fe-CNPs) which possess a hierarchical pore structure with a specific surface area as high as 1156.6 m2 g–1, much higher than the counterparts without a SiO2 coating (360.1 m2 g–1). Over these highly porous Fe-CNPs, the total current densities are more than 3 times higher than those of the lowly porous ones for the electrochemical CO2 reduction. More importantly, the maximum CO Faradaic efficiency for Fe-CNPs increases from ca. 75.0 to 98.8% in a concentrated KHCO3 solution (1 mol L–1). The porosity-induced high selectivity for CO production is also revealed on Ni-doped and Co-doped ZIF-derived CNPs, suggesting a new pathway for designing high-performance carbon catalysts through engineering the porosity for the electrochemical CO2 reduction.

Lead‐Free Piezoceramics In article number 2202307, Linglong Li, Dong Wang, and Xiaojie Lou, and co‐workers report a computationally aided composition design for discovering high‐performance lead‐free perovskite piezomaterials. The obtained bismuth sodium titanate‐based relaxor‐ferroelectric ceramic demonstrates low‐hysteresis large strains over a wide range of temperatures, which holds great promise for practical applications of actuator devices operating at room to high temperatures.