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Covalent organic frameworks (COFs) with permanent porosity, high structural stability and framework modifiability offer unique superiority for heterogeneous catalysis. Herein, we propose an in situ metallization strategy to construct a series of metal-functionalized 2D COFs (M/COFs, M = Co, Ni and Zn). The 2D matrix provides inherent accessible Lewis base sites, along with the introduced metal species acting as Lewis acid sites. These active sites with synergistic effects boost the catalytic CO2 conversion performance of these materials. Our results show that these M/COFs efficiently convert CO2 and olefins into cyclic carbonates through one-pot tandem catalysis. Specifically, Co/COFs achieve nearly complete styrene conversion and 85% yield of styrene carbonate without a co-catalyst at 80 °C and 1 bar. Simulation results further reveal the higher interaction energy of Co/COFs and guests and elucidate the underlying catalytic mechanisms of COF catalysts before and after modification. This work provides both scientific and applicational insights into designing high-performance metal-functionalized materials for optimal tandem catalytic performance. [ABSTRACT FROM AUTHOR]

One‐pot tandem synthesis of cyclic carbonates from olefins and CO2 is becoming one of the most potential strategies to fix CO2 and yield high value chemicals. However, this reaction route is in need of high performing catalysts with multifunctionalized catalytic sites in single material which is still a big challenge in one‐pot community. In this term, we combined dimension reduction and surface modification strategies to fabricate a MOF/metal complex composite, that is, Zr‐BTB/PA‐Co. In this composite, the increased Lewis base sites is capable of boosting the adsorption and activation of CO2, which further acted as nucleophilic groups to activate epoxides, while the 2D matrix offered accessible intrinsic Lewis acid sites. These advantages synergistically led to superior catalytic performance of Zr‐BTB/PA‐Co for catalyzing one‐pot reaction of olefins and CO2 under mild conditions (80°C, 1 bar, 12 h and co‐catalyst/solvent free), and even impressive catalytic activity when using CO2 directly from air. [ABSTRACT FROM AUTHOR]

Chlorinated polyfluoroalkyl ether sulfonates (F-53B) were often used as mist suppressants in the chrome plating industry, resulting in the large discharge of F-53B-containing electroplating wastewater into the aquatic environment. Due to the high toxicity of F-53B, increasing attention has been paid to its efficient removal from wastewater. In this study, three nano-activated carbons were successfully prepared from coconut shell carbons by a simple one-step KOH activation method. The nitrogen adsorption/desorption experiments showed that the synthesized coconut shell activated carbons possessed a well-developed nano-pore structure, which was favorable for the adsorption of F-53B. The results suggested that the adsorption of F-53B on the coconut shell activated carbons followed pseudo-second-order kinetics and was better fitted in the Langmuir isotherm, indicating that the adsorption of F-53B was mainly controlled by chemical adsorption and was mainly monolayer adsorption. Theoretical calculation results revealed that the faster adsorption rate of F-53B on CSAC_800 than on CSAC_600 and CSAC_700 could be contributed to the lower adsorption energy of F-53B on CSAC_800 and the higher self-diffusion coefficients of F-53B in CSAC_800. The higher adsorption capacity of CSAC_800 (qm = 537.6 mg·g−1) for F-53B than that of CSAC_600 (qm = 396.83 mg·g−1) and CSAC_700 (qm = 476.19 mg·g−1) could be attributed to the higher specific surface area and larger number of adsorption sites of CSAC_800. The results of this study demonstrate that coconut shell activated carbons with a well-developed nano-pore structure are an effective adsorbent for F-53B removal and have a good application prospect. [ABSTRACT FROM AUTHOR]