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Visible-light driven photoconversion of CO 2 into energy carriers is highly important to the natural carbon balance and sustainable development. Demonstrated here is the adenine-dependent CO 2 photoreduction performance in green biomimetic metal-organic frameworks. Photocatalytic results indicate that AD-MOF-2 exhibited a very high HCOOH production rate of 443.2 μmol g -1  h -1 in pure aqueous solution, and is more than two times higher than that of AD-MOF-1 (179.0 μmol g -1 h -1 ) in acetonitrile solution. Significantly, experimental and theoretical evidence reveal that the CO 2 photoreduction reaction mainly takes place at the aromatic nitrogen atom of adenine molecules through a unique o-amino-assisted activation rather than at the metal center. This work not only serves as an important case study for the development of green biomimetic photocatalysts used for artificial photosynthesis, but also proposes a new catalytic strategy for efficient CO 2 photoconversion., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The eCO2RR activity is correlated to the internal structural character of the catalyst. We employed two types of structural models of porphyrin-based MOFs of PCN-222(Cu) and PCN-224(Cu) into heterogeneous catalysis to illustrate the effect of structural factors on the eCO2RR performance. The composite catalyst PCN-222(Cu)/C displays better activity and selectivity (η = 450 mV, FEHCOOH = 44.3%, j = 3.2 mA cm−2) than PCN-224(Cu)/C (η = 450 mV, FEHCOOH = 34.1%, j = 2.4 mA cm−2) for the CO2 reduction to HCOOH in the range of −0.7–−0.9 V (vs. RHE) due to its higher BET surface area, CO2 uptake, and a larger pore diameter. It is interesting that PCN-224(Cu)/C displays better performance in the range of −0.4–−0.6 V (vs. RHE) due to its greater heat of adsorption, Qst and a higher affinity for CO2 molecule, which could promote the capture of CO2 onto the exposed active sites. As a result, PCN-224(Cu)/C exhibits better stability for the long-term electrolysis. [ABSTRACT FROM AUTHOR]

Visible‐light driven photoconversion of CO2 into energy carriers is highly important to the natural carbon balance and sustainable development. Demonstrated here is the adenine‐dependent CO2 photoreduction performance in green biomimetic metal–organic frameworks. Photocatalytic results indicate that AD‐MOF‐2 exhibited a very high HCOOH production rate of 443.2 μmol g−1 h−1 in pure aqueous solution, and is more than two times higher than that of AD‐MOF‐1 (179.0 μmol g−1h−1) in acetonitrile solution. Significantly, experimental and theoretical evidence reveal that the CO2 photoreduction reaction mainly takes place at the aromatic nitrogen atom of adenine molecules through a unique o‐amino‐assisted activation rather than at the metal center. This work not only serves as an important case study for the development of green biomimetic photocatalysts used for artificial photosynthesis, but also proposes a new catalytic strategy for efficient CO2 photoconversion. Eco‐friendly terms: Two biomimetic metal–organic frameworks (MOFs) were assembled with eco‐friendly components and used as photocatalysts for CO2‐to‐HCOOH conversion. One of the synthesized MOFs exhibited a very high HCOOH production rate of 443.2 μmol g−1 h−1 in pure aqueous solution. [ABSTRACT FROM AUTHOR]

Abstract An interesting chemically stable metal-organic framework, {(NC 2 H 8) 2 [Cd(DMIPA)]·xG} n (G=guest molecules of H 2 O and DMA, DMA= N , N -Dimethylacetamide) (1), featuring a 4-connected uninodal {42.64} topology and 18 Å × 18 Å snowflake-like channels along the c axis with exposed thioether groups, was assembled by employing a tetratopic polycarboxylate ligand of 5,5΄-thiobisophthalic acid (H 4 DMIPA). Ligand-based photoluminescence and solvent-dependent fluorescent intensities were exhibited in compound 1. Most strikingly, it showed remarkable sensitivity and selectivity toward Fe3+ ions under the presence of other metal ions. The photoluminescence quenching could be detected at a very low concentration of 1.62 ppm, and the maximum quenching efficiency was found to be 97.2% at 0.175 mM. Significantly, compound 1 can be recycled after use. The fluorescence intensity and quenching percentage of 1 exhibited very little changes after being used for ten successive cycles (I 0 = 6349–6093, and QP = 95.4–96.2%), indicating that 1 is a very promising MOFs-based sensor with remarkable sensitivity, selectivity, and reusability towards Fe3+ ions. Graphical abstract An interesting chemically stable metal-organic framework, {(NC 2 H 8) 2 [Cd(DMIPA)]·xG} n (G=guest molecules of H 2 O and DMA, DMA= N , N -Dimethylacetamide) (1), featuring a 4-connected uninodal {42.64} topology and 18 Å × 18 Å snowflake-like channels along the c axis with exposed thioether groups, was assembled by employing a tetratopic polycarboxylate ligand of 5,5΄-thiobisophthalic acid (H 4 DMIPA). fx1 Highlights • A chemically stable anionic framework with exposed thioether groups in the 18 Å × 18 Å snowflake-like channels was assembled. • It showed remarkable sensitivity and selectivity toward Fe3+ ions under the presence of other metal ions. • The photoluminescence quenching could be detected at a very low concentration of 1.62 ppm. • The maximum quenching efficiency was found to be 97.2% at 0.175 mM. [ABSTRACT FROM AUTHOR]

A new ɛ-Keggin polyoxometalate based metal-organic framework, [TBA] 3 [H 4 PMo 8 VMo 4 VIO 40 Zn 4 ](HTPT) 2 (1) (H 3 TPT = 1,1′:4′,1″-terphenyl-3,4″,5-tricarboxylic acid, TBA+ = tetrabutylammonium ion) was synthesized under hydrothermal conditions. The tetrahedral Zn 4 -ε-Keggin is connected through angular HTPT2− to form a 2D entangled structure with 2-fold interpenetration. The whole network displays a staggered layer structure in AB/CD/EF/GH/AB/CD/EF/GH arrangement with extensive hydrogen bonding and intermolecular interactions. More interestingly, compound 1 exhibited good hydrogen evolution reaction (HER) activity in an acidic medium, with a Tafel slope of 68 mV·dec−1 and an η 10 of 417 mV. It showed an excellent long-term stability, which could maintain its catalytic activity after 1000 cycles. [Display omitted] • A new compound has been constructed from Zn 4 -ε-Keggin node and HTPT2−. • It exhibits an interesting 2D entangled structure with 2-fold interpenetration. • The compound displays excellent catalytic ability for hydrogen evolution reaction. • After 1000 cycles, the compound can still maintain its catalytic activity. [ABSTRACT FROM AUTHOR]