The photocatalytic reduction of CO2 to energy carriers has emerged as one of the most promising strategies to alleviate the energy crisis and CO2 pollution, for which the development of catalyst was considered as the determining factor for the accomplishment of this conversion process. In this study, three stable and isostructural metal–organic frameworks (denoted as MOF-Ni, MOF-Co, and MOF-Cu) have been synthesized and used as heterogeneous catalysts in photocatalytic CO2 reduction reaction (CO2RR). It is worth noting that the MOF-Ni exhibited very high selectivity of 97.7% for photoreducing CO2 to CO, which has exceeded most of the reported MOF-based catalysts in the field. Significantly, the MOFs associated with a monometallic catalytic center offer a simple and precise structural model which allows us to understand more definitively the specific effects of different metal-ion species on photoreduction of CO2 as well as the reactive mechanism.

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Metal-organic frameworks (MOFs) with high porosity could act as an ideal substitute for supercapacitors, but their poor electrical conductivities limit their electrochemical performances. In order to overcome this problem, conductive polypyrrole (PPy) has been introduced and a novel nanocomposite resulting from polyoxometalate (POM)-based MOFs (NENU-5) and PPy has been reported. It comprises the merits of POMs, MOFs, and PPy. Finally, the highly conductive PPy covering the surfaces of NENU-5 nanocrystallines can effectively improve the electron/ion transfer among NENU-5 nanocrystallines. The optimized NENU-5/PPy nanocomposite (the volume of Py is 0.15 mL) exhibits high specific capacitance (5147 mF·cm), larger than that of pristine NENU-5 (432 mF·cm). Furthermore, a symmetric supercapacitor device based on a NENU-5/PPy-0.15 nanocomposite possesses an excellent areal capacitance of 1879 mF·cm, which is far above other MOF-based supercapacitors.

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of the 2D structures has approached its limit (< 90%) due to which the energy loss via reflection (2-5%) and thermal radiation heat loss (8-12%) occurs in all the 2D structures.One of the effective strategies for further improving the vapor-generation efficiency is to decrease the surface temperature of the absorber by increasing the surface area within a given projection area. [22] Some unprecedented vapor-generation rates have been reported in various 3D generators, which are all beyond the input solar energy limit. [23][24][25] Here, we have found that bamboos, as a natural hierarchical cellular material, can be excellent 3D solar vapor-generation devices due to their unique structural features. By a simple carbonization progress, the bamboos maintain remarkable mechanical property. Meanwhile, the carbonized bamboo-based evaporator possesses the following advantages: 1) natural hydrophilicity; 2) numerous aligned microchannels acting as highways for rapid water transport; 3) high light absorptance in a broad spectral range; 4) reduced thermal radiation heat loss; 5) lower average temperature than environment; 6) reduced vaporization enthalpy of water confined in the bamboo mesh; 7) remarkable mechanical properties; 8) ability of salt self-cleaning; 9) good scalability and low cost. As a result, a floating carbonized bamboo sample can evaporate water with an extremely high vapor-generation rate of 3.13 kg m −2 h −1 under 1 sun illumination. It also shows superior reusability and stability for solar vapor generation, without any performance degradation after cycling 360 h. The carbonized bamboo shows favorable overall performance compared with other reported solar vapor generators and has attractive applications in desalination as well asindustrial and domestic wastewater abatement. All of these features are elucidated below in detail.Bamboo is the fastest-growing and highest-yielding hierarchical cellular material on the Earth. A typical bamboo reaches maturity within months and ultimate mechanical properties within few years, making it one of the most renewable resources. [26] Figure 1a-c shows the illustration of the design concept for a bamboo-based solar vapor-generation device. Bamboo tubes with desired height were cut from the natural bamboo and were carbonized to make it dark. The carbonized Given the global challenges of water scarcity, solar-driven vapor generation has become a renewed topic as an energy-efficient way for clean water production. Here, it is revealed that bamboo, as a natural hierarchical cellular material, can be an excellent 3D solar vapor-generation device by a simple carbonization progress. A floating carbonized bamboo sample evaporates water with an extremely high vapor-generation rate of 3.13 kg m −2 h −1 under 1 sun illumination. The high evaporation rate is achieved by the unique natural structure of bamboos. The inner wall of bamboo recovers the diffuse light energy and the thermal radiation heat loss from the 3D bamboo bottom, and the outer wall captures energy from the warmer...

Dietary ferulic acid (FA), a significant antioxidant substance, is currently the subject of extensive research. FA in cereals exists mainly as feruloylated sugar ester. To release FA from food matrices, it is necessary to cleave ester cross-linking by feruloyl esterase (FAE) (hydroxycinnamoyl esterase; EC 3.1.1.73). In the present study, the FAE from a human typical intestinal bacterium, Lactobacillus acidophilus, was isolated, purified, and characterized for the first time. The enzyme was purified in successive steps including hydrophobic interaction chromatography and anion-exchange chromatography. The purified FAE appeared as a single band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with an apparent molecular mass of 36 kDa. It has optimum pH and temperature characteristics (5.6 and 37°C, respectively). Ferulic acid (FA) is a common component in plant cell walls and shows strong antioxidant potential by its radical-scavenging ability (16). In recent years, the results of many in vitro and in vivo studies have indicated that FA prevents low-density lipoprotein from oxidation (2, 27, 29, 31), exhibits inhibitory effects on tumor promotion (1, 17), and protects against certain chronic diseases such as coronary heart disease and some cancers (6,20,21,37).In cereals, FA is mainly ester linked with arabinose or galactose residues (which constitute side chains of cell wall polysaccharides) (15,18,19,28,34,38). Wende et al. showed that FA was released from 2-O-␤-D-xylopyranosyl-(5-O-feruloyl)-Larabinose by rat gut microorganisms quite quickly and presumed that feruloyl esterase (FAE) would be produced by microorganisms, with high-level activity which is closely related to the release (40). Subsequently, other in vitro observations confirmed the existence of FAE in animal and human intestines (3, 23). These results suggest that FAE plays an important role in releasing free FA from different feruloylated forms in foodstuff in the gut.Although FAEs from some eukaryotic cells (4,7,11,12,14,22,26,39) and from only one prokaryotic cell (13) have been purified and characterized to date, there is no information about FAE from intestinal bacteria. It is reported that FAEs from various sources show different properties with respect to such characteristics as optimal temperature and optimal pH. Therefore, it is necessary to purify the FAE from human gut bacteria to further study the mechanism of release of FA from complex food matrices in vitro. Nishizawa et al. studied the FAE activities of typical intestinal bacteria and found that among the intestinal bacteria tested, Lactobacillus acidophilus exhibited the highest level of activity with respect to feruloylated arabinose ester (30).Some investigations indicate that the presence of xylanase enhances FAE activity. In most of these studies, however, destarched wheat bran was used as a substrate; these experiments could not supply sufficiently detailed information to explain the releasing mechanism of dietary FA and the interaction between xylanase and FAE to ...

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