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Elaborately designed multifunctional electrocatalysts capable of promoting Li+ and CO2 transport are essential for upgrading the cycling stability and rate capability of Li‐CO2 batteries. Hydrogen‐bonded organic frameworks (HOFs) with open channels and easily functionalized surfaces hold great potential for applications in efficient cathodes of Li‐CO2 batteries. Herein, a robust HOFS (HOF‐FJU‐1) is introduced for the first time as a co‐catalyst in the cathode material of Li‐CO2 batteries. HOF‐FJU‐1 with cyano groups located periodically in the pore can induce homogeneous deposition of discharge products and accommodate volumetric expansion of discharge products during cycling. Besides, HOF‐FJU‐1 enables effective interaction between Ru0 nanoparticles and cyano groups, thus forming efficient and uniform catalytic sites for CRR/CER. Moreover, HOF‐FJU‐1 with regularly arranged open channels are beneficial for CO2 and Li+ transport, enabling rapid redox kinetic conversion of CO2. Therefore, the HOF‐based Li‐CO2 batteries are capable of stable operation at 400 mA g−1 for 1800 h and maintain a low overpotential of 1.96 V even at high current densities up to 5 A g−1. This work provides valuable guidance for developing multifunctional HOF‐based catalysts to upgrade the longevity and rate capability of Li‐CO2 batteries. [ABSTRACT FROM AUTHOR]

Ag nanoclusters have received increasing attention due to their atomically precise and diverse structures and intriguing optical properties. Nevertheless, the inherent instability of Ag nanoclusters has seriously hindered their practical application. In this work, for the first time, Ag clusters are collaboratively protected by hydrophobic Ti‐oxo clusters and alkyne ligands. Initially, a pyramidal Ag5 cluster terminated with tBuC≡C− and CH3CN was inserted into the cavity of a Ti8‐oxo nanoring to form Ag5@Ti8. To overcome the instability of acetonitrile‐terminated silver site, such two Ag5@Ti8 clusters could sandwich an Ag4 unit to form Ag14‐nanorod@Ti16‐oxo‐nanoring (Ag14@Ti16), which is peripherally protected by fluorophenyl groups and alkyne caps. This threefold protected (hydrophobic fluorinated organic layer, Ti‐O shell, and terminal alkyne ligands) Ag14@Ti16 exhibits superhydrophobicity and excellent ambient stability, endowing it with solid‐state optical limiting characteristics. [ABSTRACT FROM AUTHOR]