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Chemical carbon dioxide (CO 2) fixation over heterogenous catalysts under more realistic conditions enables the acceleration of the global carbon cycle. Despite the recent advances, many catalysts often suffer from chemical lability, mass transfer resistance, as well as single catalytic species. To this end, this work demonstrates a metal-organic framework (MOF)-templated thermolysis to give bimetallic oxides, Cu x Zn y -BMOs, featuring hierarchically porous structures. By varying the initial molar ratio of Cu/Zn, the local coordination environment can be adjusted, thus regulating the type and quantity of active species. Together with its abundant active sites and appropriate pore size, the optimized Cu 1 Zn 2 -BMO not only achieves a high activity (98% yield) for the coupling of CO 2 and epichlorohydrin under solvent-free mild conditions, but also promotes the N-formylation of CO 2 with amines. Worthy to note, the decent chemical stability endows Cu 1 Zn 2 -BMO with almost unchanged performance even after long exposure to humidity. Our study offers a reliable strategy for the structure regulation of catalysts to enhance practical CO 2 catalytic conversion. [Display omitted] • Synthesis of hierarchically porous bimetallic oxides by a MOF-templated process. • Surface active species can be adjusted by varying the initial molar ratio of Cu/Zn. • Cu 1 Zn 2 -BMO shows high activity for CO 2 cycloaddition and N-formylation of CO 2 with amines. • High yield can be maintained even after a long-time moisture exposure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zn x Fe y -ZIF/MXene catalysts have been fabricated by an in situ growth method. • MXene acts as a light harvester to extend the light absorption of bimetallic ZIF. • A high yield (96%) is obtained by Zn20Fe1-ZIF/MXene for solar driven CO2 fixation. • The catalytic activity can be maintained under simulated flue gas conditions. • photo-induced photo-thermal catalytic mechanism has been investigated. Photodriven CO 2 conversion has been widely recognized as an effective pathway for achieving carbon neutrality. In this paper, we demonstrate the immobilization of bimetallic Zn/Fe ZIF onto the surface of Ti 3 C 2 T x MXene via an in situ growth process for photodriven solvent-free CO 2 cycloaddition. MXene can extend the optical response of bimetallic ZIF into the near-infrared region. In turn, the incorporated MOF particles effectively prevent the layers of MXene from stacking. The resulting Zn 20 Fe 1 -ZIF/MXene has improved activity (96% yield) in the cycloaddition of epichlorohydrin with 1 bar CO 2 under full spectrum illumination (350 mW/cm2) for 6 h, ca. 3.4, 1.7, and 1.2 times higher than those of pure Zn 20 Fe 1 -ZIF, MXene, and the physical mixture, respectively. Besides, this hybrid catalyst provides desirable stability and performance even after several catalytic cycles, exposure to humid environment or under diluted CO 2 (15%). Control experiments and infrared thermography reveal the synergistic photocatalytic-photothermal contribution of hybrid materials to the photoinduced CO 2 fixation. Our research offers a facile method to construct MOF containing photocatalysts for application of CO 2 conversion with high practical utility. [ABSTRACT FROM AUTHOR]

Macroscopic MOF-based forests have been rationally fabricated via metal template-guided growth strategy for promoting CO 2 chemical transformation. [Display omitted] • A metal template-guided growth strategy is developed to give MOF forests. • ZIF-8 forests show superb catalytic performances toward CO 2 cycloaddition. • ZIF-8 forests can be easily recovered and reused at least ten times. • Activity can be maintained under mimic flue gas conditions or light irradiation. Construction of macroscopic metal–organic frameworks (MOFs) with high processability is crucial for their practical usage. Here, we demonstrate a facile metal template-guided growth approach that exploits the synthesis of forest-like ZIF-8-based material. The 3D self-supported array architecture endows the resultant ZIF-8 forests with efficient exposure of active sites, rapid mass transfer and simple recovery. Under mild catalytic reaction conditions (1 bar CO 2 , 60 ℃), ZIF-8 forests show remarkable activities toward the coupling of epoxides and CO 2 with an excellent cyclic carbonate yield of 96%, surpassing the powdered ZIF-8 crystals. Importantly, the catalytic performance can be well-maintained even after 10 cycles and under both simulated flue gas conditions and full-spectrum light irradiation, demonstrating the potential for practical catalysis. Our work provides a practical guideline to produce macroscopic MOF-based materials with great potential for industrial catalysis. [ABSTRACT FROM AUTHOR]