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The capture of radioactive I 2 vapor from nuclear waste under industrial operating conditions remains a challenging task, as the practical industrial conditions of high temperature (≥150 °C) and low I 2 concentration (∼150 ppmv) are unfavorable for I 2 adsorption. We report a novel guanidinium-based covalent organic framework (COF), termed TGDM, which can efficiently capture I 2 under industrial operating conditions. At 150 °C and 150 ppmv I 2 , TGDM exhibits an I 2 uptake of ∼30 wt %, which is significantly higher than that of the industrial silver-based adsorbents such as Ag@MOR (17 wt %) currently used in the nuclear fuel reprocessing industry. Characterization and theoretical calculations indicate that among the multiple types of adsorption sites in TGDM, only ionic sites can bond to I 2 through strong Coulomb interactions under harsh conditions. The abundant ionic groups of TGDM account for its superior I 2 capture performance compared to various benchmark adsorbents. In addition, TGDM exhibits exceptionally high chemical and thermal stabilities that fully meet the requirements of practical radioactive I 2 capture (high-temperature, humid, and acidic environment) and differentiate it from other ionic COFs. Furthermore, TGDM has excellent recyclability and low cost, which are unavailable for the current industrial silver-based adsorbents. These advantages make TGDM a promising candidate for capturing I 2 vapor during nuclear fuel reprocessing. This strategy of incorporating chemically stable ionic guanidine moieties in COF would stimulate the development of new adsorbents for I 2 capture and related applications.

Rechargeable Li–CO2 batteries have attracted worldwide attention due to the capability of CO2 capture and superhigh energy density. However, they still suffer from poor cycling performance and huge overpotential. Thus, it is essential to explore highly efficient catalysts to improve the electrochemical performance of Li–CO2 batteries. Here, phytic acid (PA)‐cross‐linked ruthenium complexes and melamine are used as precursors to design and synthesize RuP2 nanoparticles highly dispersed on N, P dual‐doped carbon films (RuP2‐NPCFs), and the obtained RuP2‐NPCF is further applied as the catalytic cathode for Li–CO2 batteries. RuP2 nanoparticles that are uniformly deposited on the surface of NPCF show enhanced catalytic activity to decompose Li2CO3 at low charge overpotential. In addition, the NPCF its with porous structure in RuP2‐NPCF provides superior electrical conductivity, high electrochemical stability, and enough ion/electron and space for the reversible reaction in Li–CO2 batteries. Hence, the RuP2‐NPCF cathode delivers a superior reversible discharge capacity of 11951 mAh g−1, and achieves excellent cyclability for more than 200 cycles with low overpotentials (<1.3 V) at the fixed capacity of 1000 mAh g−1. This work paves a new way to design more effective catalysts for Li–CO2 batteries.

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Co@Co3O4@NC-900 is designed and used as a catalyst for bulk and flexible Zn–air batteries which display good electrochemical performance.