Search

Combining theoretical prediction and experimental exploration, the first sandwich-type polyoxovanadoborate (POVB) with an odd number of nuclei, [V11B26O73(OH)10]8−(1), was discovered under hydrothermal conditions. Density-functional theory (DFT) gives a rationalization for the existence of this structure and the structural feature is consistent with the {VNB2N+X} (X = 2, 4, 6, 8) general formula. Excitingly, when Co and 1,10-phenanthroline (phen) are introduced into the synthesis of vanadoborates system, a 100-nuclei [Co6(phen)10(H2O)8][V14Co12B72O144(OH)20]·28H2O (2) and a 102-nuclei [Co6(phen)14(H2O)4][V14Co12B72O144 (OH)20]·23H2O (3) with the same core structure of [V14Co12B72]12− are obtained. The vase-shaped [V14Co12B72] polyanion is a multilayered sandwich-type structure containing seven distinct structural layers and is the largest known POVB. Furthermore, 2 demonstrates exceptional thermal and chemical stability and serves as an efficient and stable catalyst for the photoreduction of carbon dioxide. [ABSTRACT FROM AUTHOR]

Covalent organic polymers (COPs) received much attention due to their application in diverse fields, especially in sensing. A highly efficient fluorescence sensor in selective detection of Fe3+ ions is necessary to develop. In this work, we successfully synthesized a new covalent organic polymers named COP-TP, with the excellent performance in selective detection of Fe3+ ions, the quenching mechanism mainly due to the energy transfer process. The above results show COP-TP has the possibility to be a new candidate in selective detection as Fe3+ ions sensor.

Precise synthesis of polyoxometalates (POMs) is important for the fundamental understanding of the relationship between the structure and function of each building motif. However, it is a great challenge to realize the atomic-level tailoring of specific sites in POMs without altering the major framework. Herein, we report the case of Ce-mediated molecular tailoring on gigantic {Mo132}, which has a closed structural motif involving a never seen {Mo110} decamer. Such capped wheel {Mo132} undergoes a quasi-isomerism with known {Mo132} ball displaying different optical behaviors. Experiencing an 'Inner-On-Outer' binding process with the substituent of {Mo2} reactive sites in {Mo132}, the site-specific Ce ions drive the dissociation of {Mo2*} clipping sites and finally give rise to a predictable half-closed product {Ce11Mo96}. By virtue of the tailor-made open cavity, the {Ce11Mo96} achieves high proton conduction, nearly two orders of magnitude than that of {Mo132}. This work offers a significant step toward the controllable assembly of POM clusters through a Ce-mediated molecular tailoring process for desirable properties. Polyoxometalates (POMs) are molecular clusters with diverse structures. Here authors present the synthesis of POMs by Ce-mediated molecular tailoring from gigantic {Mo132} into half-closed {Ce11Mo96}, with proton conductivity nearly two orders of magnitude higher than {Mo132}. [ABSTRACT FROM AUTHOR]

The CO2 emissions from flue gases in traditional electricity generation and industrial sectors account for the main source of global emissions. The direct conversion of CO2 in flue gases into value-added carbon production is a low-cost and simple process to realize a carbon neutral cycle, yet the development of an efficient catalyst to treat the CO2 in flue gases is still in its infancy. Here, we present two polyoxometalate-based metal organic frameworks (POMOFs) with [W10O32]4− as the connecting node, named Co2(W10O32)(BIA)4(CH3CN)4 (compound 1) and Co4(W10O32)(INA)6(CH3CN)4(TBA)2 (compound 2), as catalysts for the photoreduction of CO2 in exhaust gases. Under a pure CO2 atmosphere, syngas is the main product and the yield of compound 1 is 72.7 μmol h−1, which is ∼40% higher than that of compound 2 (54.2 μmol h−1). Notably, the yield of compound 1 reaches 42.7 μmol h−1 with 15% CO2 in the flue gas, which indicates that the catalyst can not only overcome the low CO2 concentration but also tolerate the harsh gas composition in the flue gas. In addition, density functional theory (DFT) calculations show that the charge distribution and steric hindrance of compound 1 were conducive to the reduction reaction. [ABSTRACT FROM AUTHOR]

Influenza A viruses (IAV) still pose a threat to animals and humans. Currently, M2 protein ion channel inhibitors and neuraminidase inhibitors are the two main drugs for treating IAV infections by interrupting virus assembly or release respectively, but the emergence of viral resistance was a concern for their long term uses. In this study, the inhibition effect of alpha-lipoic acid (α-LA) on IAV propagation has been evaluated in vitro. The results showed that α-LA inhibited IAV replication in MDCK cells at 2mM, and also reduced nucleus translocation of nuclear factor κB (NF-κB) p65 at the concentration above 1mM. Additionally, it was found that caspase-3 activity was remarkably inhibited and type I interferons (IFNs) were up-regulated following α-LA treatment. This study indicated that α-LA might be a potential anti-influenza virus agent worthy of further investigations.

Comprehensive Summary: Photocatalytic CO2 reduction to fuels and chemicals has been considered as the promising avenue to realize carbon resource recycling. Covalent organic frameworks (COFs) with pre‐designed and tailorable structures are promising platforms for studying the influence of the microenvironment of catalysts on photocatalytic CO2 reduction. Herein, we report three isomorphic COFs (TPHH‐COF, TPPD‐COF and TPBD‐COF) as heterogeneous photocatalysts for CO2 reduction and investigate the different levels of conjugation and planarity of COFs effect on the catalytic activity. Photoelectrochemical measurements show that TPPD‐COF has a narrower band gap and faster photocurrent response compared to TPHH‐COF and TPBD‐COF, probably due to the moderate conjugation and planarity. As the photocatalyst, TPPD‐COF showed the most outstanding photocatalytic activity with the production rates of 951 and 157 μmol·g–1·h–1 for CO and H2, respectively. This study illustrates the close relation between microenvironment and photocatalytic activity and provides new insights for designing high‐performance photocatalysts. [ABSTRACT FROM AUTHOR]

Direct conversion of diluted CO2 to value-added chemical stocks and fuels with solar energy is an energy-saving approach to relieve global warming and realize a carbon-neutral cycle. The exploration of catalysts with both efficient CO2 adsorption and reduction ability is significant to achieving this goal. Metal–organic frameworks (MOFs) are emerging in the field of low-concentration CO2 reduction due to their highly tunable structure, high porosity, abundant active sites and excellent CO2 adsorption capacity. This highlight outlines the advantages of MOFs for low-pressure CO2 adsorption and the strategies to improve the photocatalytic performance of MOF materials at low CO2 concentrations, including the functionalization of organic ligands, regulation of metal nodes and preparation of MOF composites or derivatives. This paper aims to provide possible avenues for the rational design and development of catalysts with the ability to reduce low-concentration CO2 efficiently for practical applications. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]