Smart surface coatings of silicon (Si) nanoparticles are shown to be good examples for dramatically improving the cyclability of lithium-ion batteries. Most coating materials, however, face significant challenges, including a low initial Coulombic efficiency, tedious processing, and safety assessment. In this study, a facile sol-gel strategy is demonstrated to synthesize commercial Si nanoparticles encapsulated by amorphous titanium oxide (TiO ), with core-shell structures, which show greatly superior electrochemical performance and high-safety lithium storage. The amorphous TiO shell (≈3 nm) shows elastic behavior during lithium discharging and charging processes, maintaining high structural integrity. Interestingly, it is found that the amorphous TiO shells offer superior buffering properties compared to crystalline TiO layers for unprecedented cycling stability. Moreover, accelerating rate calorimetry testing reveals that the TiO -encapsulated Si nanoparticles are safer than conventional carbon-coated Si-based anodes.

The application of high‐performance silicon‐based anodes, which are among the most prominent anode materials, is hampered by their poor conductivity and large volume expansion. Coupling of silicon‐based anodes with carbonaceous materials is a promising approach to address these issues. However, the distribution of carbon in reported hybrids is normally inhomogeneous and above the nanoscale, which leads to decay of coulombic efficiency during deep galvanostatic cycling. Herein, we report a porous silicon‐based nanocomposite anode derived from phenylene‐bridged mesoporous organosilicas (PBMOs) through a facile sol–gel method and subsequent pyrolysis. PBMOs show molecularly organic–inorganic hybrid character, and the resulting hybrid anode can inherit this unique structure, with carbon distributed homogeneously in the Si‐O‐Si framework at the atomic scale. This uniformly dispersed carbon network divides the silicon oxide matrix into numerous sub‐nanodomains with outstanding structural integrity and cycling stability.

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