Bimetallic Ni/Mg-MOF-74 was reported as a catalyst for efficient CO2 photoreduction from simulated flue gas to generate value-added formate.

Converting industrial exhaust into valuable chemicals is crucial for sustainable economic development. Direct CO2 photoreduction from real flue gas is an ideal clean and promising way, until now, without success. Here, photoreduction of exhaust gas from the power plant by Ni bridged COF (Ni@TPHH‐COF) is shown. Under visible light, syngas is produced with CO output reaching 2.1 mol kg−1 h−1. The ideal conversion of flue gas is up to 672 L kg−1 h−1. Of note, the system exhibits appealing yield and selectivity under 0.5–40% CO2 and AQY achieves 3.96% under 10% CO2, ranking among the highest value of reported photocatalysts. Mechanism studies suggest CO2 plays a dual function as both a component of a catalytic site and a reactant, which can not only selectively enrich CO2 in catalytic sites but improve reaction rate significantly. This CO2‐dominated bifunctional site prolongs electrons lifetime, stabilizes intermediates, and reduces free energy of reduction under diluted CO2.

The rational design and construction of multifunctional electrocatalysts with high activity, low cost, and outstanding stability are highly desirable for the development of renewable energy but are still a big challenge. Bimetallic catalysts are a kind of promising candidates, like the hybrids of Co and VN nanoparticles (Co/VN). However, the inevitable aggregation during the preparation and electrochemical process lowers their reactivity and durability. Herein, small Co/VN nanoparticles (4–8 nm) embedded in porous graphitic carbon layers (Co/VN NPs@C) were obtained through the pyrolysis of metal–organic frameworks (MOFs). The synergistic effect of in situ generated Co and VN NPs together with fast electron transfer from graphitic carbon layers renders this catalyst to possess excellent trifunctional performance. More attractively, Co/VN NPs@C as both the anode and the cathode shows a low voltage of 1.58 V when the current density is up to 10 mA cm–2, exceeding most electrocatalysts based on non-noble metals. The rechargeable Zn–air batteries constructed by Co/VN NPs@C deliver high round-trip efficiency together with a peak power density of 130 mW cm–2, a specific capacity of 757 mAh g–1, and desirable stability, outperforming the traditional Zn–air batteries based on the Pt/C and RuO2 pair. This work opens a promising avenue toward constructing highly effective multifunctional electrocatalysts by designing small-sized nanoparticles with various active sites derived from MOFs.

The design of efficient and inexpensive photocatalysts for CO 2 photoreduction under visible light is of great significance for the sustainable development of the entire society. Herein, a copper-based metal−organic framework (MOF) (CUST-804) using a bulky tetraphenylethylene-tetrazole linker is synthesized and successfully used as a photocatalyst for CO 2 reduction. The structural characterizations, as well as the photophysical properties, are investigated systematically. In the heterogeneous catalytic system, CUST-804 exhibits a robust CO production activity up to 2.71 mmol g −1 h −1 with excellent recyclability along with a selectivity of 82.8%, which is comparable with those of the reported copperbased MOF system. Theoretical calculations demonstrated that, among three kinds of coordinated model, only the 5-coordinated Cu site is active for CO 2 reduction, in which the *COOH intermediate is stabilized and CO is readily desorbed. The results obtained herein can provide fresh insights into the realization of efficient copper-functionalized crystalline photocatalysts for CO 2 reduction.