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Rational design of robust photocatalytic systems to direct capture and in-situ convert diluted CO 2 from flue gas is a promising but challenging way to achieve carbon neutrality. Here, we report a new type of host-guest photocatalysts by integrating CO 2 -enriching ionic liquids and photoactive metal-organic frameworks PCN-250-Fe 2 M (M = Fe, Co, Ni, Zn, Mn) for artificial photosynthetic diluted CO 2 reduction in gas-solid phase. As a result, [Emim]BF 4 (39.3 wt%)@PCN-250-Fe 2 Co exhibits a record high CO 2 -to-CO reduction rate of 313.34 μmol g -1 h -1 under pure CO 2 atmosphere and 153.42 μmol g -1 h -1 under diluted CO 2 (15%) with about 100% selectivity. In scaled-up experiments with 1.0 g catalyst and natural sunlight irradiation, the concentration of pure and diluted CO 2 (15%) could be significantly decreased to below 85% and 10%, respectively, indicating its industrial application potential. Further experiments and theoretical calculations reveal that ionic liquids not only benefit CO 2 enrichment, but also form synergistic effect with Co 2+ sites in PCN-250-Fe 2 Co, resulting in a significant reduction in Gibbs energy barrier during the rate-determining step of CO 2 -to-CO conversion., (© 2024. The Author(s).)

The connectivity (valency) of building blocks for constructing 3D covalent organic frameworks (COFs) has long been limited to 4, 6, 8, and 12. Developing a higher connectivity remains a great challenge in the field of COF structural design. Herein, this work reports a hierarchical expansion strategy for making 16-connected building blocks to construct 3D COFs with sqc topology. The [16 + 2] construction achieved by condensation between a 16-connected carbazolyl dicyanobenzene-based building block (CzTPN) and linear diamino linkers (BD or Bpy) affords two 3D COFs (named CzBD COF and CzBpy COF). Furthermore, attributed to the well-organized donor-acceptor (D-A) heterojunction, the Ni chelated CzBpy COF (Ni@CzBpy COF) exhibits excellent performance for photoredox/Ni dual catalytic C(sp 3 )-C(sp 2 ) cross-coupling of alkyltrifluoroborates with aryl halides, achieving a maximum 98% conversion and 94% yield for various substrates. This work developed the first case of high-connectivity COFs bearing 16-connected units, which is the highest connectivity reported until now, and achieved efficient photocatalysis applications, thus greatly enriching the possibilities of COFs.

When catalytic reactions are interfered with by radiation sources, thorium clusters are promising as potential catalysts due to their superior radiation resistance. However, there is currently very little research on the design synthesis and catalytic application of radiation-stable thorium clusters. In this work, we have elaborately engineered and fabricated three high-nuclear thorium cluster catalysts denoted as Th 12 L 3 -MA 12 , Th 12 L 3 -MA 6 -BF 6 , and Th 12 L 3 -Fcc 12 , which did not undergo any significant alterations in their molecular structures and compositions after irradiation with 690 kGy γ-rays. We systematically investigated the photocatalytic/thermocatalytic properties of these radiation-resistant thorium clusters for the first time and found that γ-rays could not alter their catalytic activities. In addition, it was found that ligand engineering could modulate the catalytic activity of thorium clusters, thus expanding the range of catalytic applications of thorium clusters, including reduction reactions (nitroarene reduction) and some oxidation reactions (N-heterocyclic oxidative dehydrogenation and diphenylmethane oxidation). Meanwhile, all of these organic transformation reactions achieved a >80% conversion and nearly 100% product selectivity. Radiation experiments combined with DFT calculations showed that the synergistic catalysis of thorium-oxo core and ligands led to the generation of specific active species (H + , O 2 •- , or t BuO/ t BuOO • ) and activation of substrate molecules, thus achieving superior catalytic performance. This work is not only the first to develop radiation-resistant thorium cluster catalysts to perform efficient redox reactions but also provides design ideas for the construction of high-nuclearity thorium clusters under mild conditions.

The Zr(IV) ions are easily hydrolyzed to form oxides, which severely limits the discovery of new structures and applications of Zr-based compounds. In this work, three ferrocene (Fc)-functionalized Zr-oxo clusters (ZrOCs), Zr 9 Fc 6 , Zr 10 Fc 6 and Zr 12 Fc 8 were synthesized through inhibiting the hydrolysis of Zr(IV) ions, which show increased nuclearity and regular structural variation. More importantly, these Fc-functionalized ZrOCs were used as heterogeneous catalysts for the transfer hydrogenation of levulinic acid (LA) and phenol oxidation reactions for the first time, and displayed outstanding catalytic activity. In particular, Zr 12 Fc 8 with the largest number of Zr active sites and Fc groups can achieve > 95% yield for LA-to-γ-valerolactone within 4 h (130 °C) and > 98% yield for 2,3,6-trimethylphenol-to-2,3,5-trimethyl-p-benzoquinone within 30 min (80 °C), showing the best catalytic performance. Catalytic characterization combined with theory calculations reveal that in the Fc-functionalized ZrOCs, the Zr active sites could serve as substrate adsorption sites, while the Fc groups could act as hydrogen transfer reagent or Fenton reagent, and thus achieve effectively intramolecular metal-ligand synergistic catalysis. This work develops functionalized ZrOCs as catalysts for thermal-triggered redox reactions., (Copyright © 2024 Science China Press. Published by Elsevier B.V. All rights reserved.)

Although photocatalytic C-H activation has been realized by using heterogeneous catalysts, most of them require high-temperature conditions to provide the energy required for C-H bond breakage. The catalysts with photothermal conversion properties can catalyze this reaction efficiently at room temperature, but so far, these catalysts have been rarely developed. Here, we construct bifunctional catalysts Rh-COF-316 and -318 to combine photosensitive covalent organic frameworks (COFs) and transition-metal catalytic moiety using a post-synthetic approach. The Rh-COF enable the heterogeneous C-H activation reaction by photothermal conversion for the first time, and exhibit excellent yields (up to 98 %) and broad scope of substrates in [4+2] annulation at room temperature, while maintaining the high stability and recyclability. Significantly, this work is the highest yield reported so far in porous materials catalyzing C(sp 2 )-C(sp 2 ) formation at room temperature. The excellent performances can be attributed to the COF-316, which enhances the photothermal effect (ΔT=50.9 °C), thus accelerating C-H bond activation and the exchange of catalyst with substrates., (© 2024 Wiley‐VCH GmbH.)

Integrating the advantages of homogeneous and heterogeneous catalysis has proved to be an optimal strategy for developing catalytic systems with high efficiency, selectivity, and recoverability. Supramolecular metal-organic cages (MOCs), assembled by the coordination of metal ions with organic linkers into discrete molecules, have performed solvent processability due to their tunable packing modes, endowing them with the potential to act as homogeneous or heterogeneous catalysts in different solvent systems. Here, the design and synthesis of a series of stable {Cu 3 } cluster-based tetrahedral MOCs with varied packing structures are reported. These MOCs, as homogeneous catalysts, not only show high catalytic activity and selectivity regardless of substrate size during the CO 2 cycloaddition reaction, but also can be easily recovered from the reaction media through separating products and co-catalysts by one-step work-up. This is because that these MOCs have varied solubilities in different solvents due to the tunable packing of MOCs in the solid state. Moreover, the entire catalytic reaction system is very clean, and the purity of cyclic carbonates is as high as 97% without further purification. This work provides a unique strategy for developing novel supramolecular catalysts that can be used for homogeneous catalysis and recycled in a heterogeneous manner., (© 2024 Wiley‐VCH GmbH.)

Objective: The purpose of this study was to investigate the bacterial communities of biting midges and ticks collected from three sites in the Poyang Lake area, namely, Qunlu Practice Base, Peach Blossom Garden, and Huangtong Animal Husbandry, and whether vectors carry any bacterial pathogens that may cause diseases to humans, to provide scientific basis for prospective pathogen discovery and disease prevention and control., Methods: Using a metataxonomics approach in concert with full-length 16S rRNA gene sequencing and operational phylogenetic unit (OPU) analysis, we characterized the species-level microbial community structure of two important vector species, biting midges and ticks, including 33 arthropod samples comprising 3,885 individuals, collected around Poyang Lake., Results: A total of 662 OPUs were classified in biting midges, including 195 known species and 373 potentially new species, and 618 OPUs were classified in ticks, including 217 known species and 326 potentially new species. Surprisingly, OPUs with potentially pathogenicity were detected in both arthropod vectors, with 66 known species of biting midges reported to carry potential pathogens, including Asaia lannensis and Rickettsia bellii , compared to 50 in ticks, such as Acinetobacter lwoffii and Staphylococcus sciuri . We found that Proteobacteria was the most dominant group in both midges and ticks. Furthermore, the outcomes demonstrated that the microbiota of midges and ticks tend to be governed by a few highly abundant bacteria. Pantoea sp7 was predominant in biting midges, while Coxiella sp1 was enriched in ticks. Meanwhile, Coxiella spp., which may be essential for the survival of Haemaphysalis longicornis Neumann, were detected in all tick samples. The identification of dominant species and pathogens of biting midges and ticks in this study serves to broaden our knowledge associated to microbes of arthropod vectors., Conclusion: Biting midges and ticks carry large numbers of known and potentially novel bacteria, and carry a wide range of potentially pathogenic bacteria, which may pose a risk of infection to humans and animals. The microbial communities of midges and ticks tend to be dominated by a few highly abundant bacteria., (Copyright © 2024 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.)

The striking aesthetic appeal of fullerene-like clusters has captured the interest of researchers. Nevertheless, the assembly of fullerene-like polyoxovadanadate (POV) cages remains a significant challenge due to the scarcity of suitable pentagonal motif. Herein, we have successfully synthesized the first fullerene-like all-inorganic POV cage, {(V 2 O)V 30 Nb 12 O 102 (H 2 O) 12 } (V 30 Nb 12 ), by introducing Nb into the POVs. V 30 Nb 12 is assembled by 12 heterometallic {(Nb)V 5 } pentagons through sharing V centers with I h symmetry, reminiscent of C 60 . To our knowledge, the fullerene-like V 30 Nb 12 not only represents the highest-nuclearity POV cage but also stands as the first niobovanadate cluster. Notably, V 30 Nb 12 exhibits excellent solution stability, as confirmed by ESI-MS, FT-IR and UV/Vis spectra. As there is no protection organic ligand on its outer surface, V 30 Nb 12 can be further modified with Cu-complexes to form a fullerene-like cluster based zigzag chain (Cu-V 30 Nb 12 )., (© 2024 Wiley-VCH GmbH.)

In modern industries, the aerobic oxidation of C(sp 3 )-H bonds to achieve the value-added conversion of hydrocarbons requires high temperatures and pressures, which significantly increases energy consumption and capital investment. The development of a light-driven strategy, even under natural sunlight and ambient air, is therefore of great significance. Here we develop a series of hetero-motif molecular junction photocatalysts containing two bifunctional motifs. With these materials, the reduction of O 2 and oxidation of C(sp 3 )-H bonds can be effectively accomplished, thus realizing efficient aerobic oxidation of C(sp 3 )-H bonds in e.g., toluene and ethylbenzene. Especially for ethylbenzene oxidation reactions, excellent catalytic capacity (861 mmol g cat -1 ) is observed. In addition to the direct oxidation of C(sp 3 )-H bonds, CeBTTD-A can also be applied to other types of aerobic oxidation reactions highlighting their potential for industrial applications., (© 2024. The Author(s).)

Spectral combination is promising for diffraction-limited beam quality and single aperture beams. Unfortunately, beamlet deviations, linewidth broadening, and thermal aberrations inevitably degrade the beam quality. Many high-power laser systems integrate adaptive optics systems to maintain beam qualities. However, owing to the nature of incoherent combination, there is no well-defined wavefront in the spectrally combined beam, and whether phase compensations can enhance beam quality has not been discussed yet. We present the feasibility of improving the beam quality of spectral combined fiber lasers by adaptive optics. Simulations indicate that common path aberrations can be effectively corrected by adaptive optics, while beam quality degraded by displacement deviations and linewidth broadening cannot be improved. Additionally, the combined beam could be directly used as the beacon light in the propagation tunnel. To our knowledge, this study is the first to demonstrate that adaptive optics can improve the beam quality of spectrally combined fiber lasers and enable a further step toward diffraction-limited beam quality.

Artificial photosynthetic diluted CO 2 reduction directly driven by natural sunlight is a challenging, but promising way to realize carbon-resources recycling utilization. Herein, a three-in-one photocatalytic system of CO 2 enrichment, CO 2 reduction and H 2 O oxidation sites is designed for diluted CO 2 reduction. A Zn-Salen-based covalent organic framework (Zn-S-COF) with oxidation and reductive sites is synthesized; then, ionic liquids (ILs) are loaded into the pores. As a result, [Emim]BF 4 @Zn-S-COF shows a visible-light-driven CO 2 -to-CO conversion rate of 105.88 µmol g -1 h -1 under diluted CO 2 (15%) atmosphere, even superior than most photocatalysts in high concentrations CO 2 . Moreover, natural sunlight driven diluted CO 2 reduction rate also reaches 126.51 µmol g -1 in 5 h. Further experiments and theoretical calculations reveal that the triazine ring in the Zn-S-COF promotes the activity of H 2 O oxidation and CO 2 reduction sites, and the loaded ILs provide an enriched CO 2 atmosphere, realizing the efficient photocatalytic activity in diluted CO 2 reduction., (© 2023 Wiley-VCH GmbH.)

Photocatalytic synthesis of hydrogen peroxide (H 2 O 2 ) is a potential clean method, but the long distance between the oxidation and reduction sites in photocatalysts hinders the rapid transfer of photogenerated charges, limiting the improvement of its performance. Here, a metal-organic cage photocatalyst, Co 14 (L-CH 3 ) 24 , is constructed by directly coordinating metal sites (Co sites) used for the O 2 reduction reaction (ORR) with non-metallic sites (imidazole sites of ligands) used for the H 2 O oxidation reaction (WOR), which shortens the transport path of photogenerated electrons and holes, and improves the transport efficiency of charges and activity of the photocatalyst. Therefore, it can be used as an efficient photocatalyst with a rate of as high as 146.6 μmol g -1  h -1 for H 2 O 2 production under O 2 -saturated pure water without sacrificial agents. Significantly, the combination of photocatalytic experiments and theoretical calculations proves that the functionalized modification of ligands is more conducive to adsorbing key intermediates (*OH for WOR and *HOOH for ORR), resulting in better performance. This work proposed a new catalytic strategy for the first time; i.e., to build a synergistic metal-nonmetal active site in the crystalline catalyst and use the host-guest chemistry inherent in the metal-organic cage (MOC)to increase the contact between the substrate and the catalytically active site, and finally achieve efficient photocatalytic H 2 O 2 synthesis., (© 2023 Wiley-VCH GmbH.)

Electrocatalytic CO 2 reduction (ECR) coupled with organic oxidation is a promising strategy to produce high value-added chemicals and improve energy efficiency. However, achieving the efficient redox coupling reaction is still challenging due to the lack of suitable electrocatalysts. Herein, we designed two bifunctional polyimides-linked covalent organic frameworks (PI-COFs) through assembling phthalocyanine (Pc) and porphyrin (Por) by non-toxic hydrothermal methods in pure water to realize the above catalytic reactions. Due to the high conductivity and well-defined active sites with different chemical environments, NiPc-NiPor COF performs efficient ECR coupled with methanol oxidation reaction (MOR) (Faradaic efficiency of CO (FE CO ) = 98.12%, partial current densities of CO (j CO ) = 6.14 mA cm -2 for ECR, FE HCOOH  = 93.75%, j HCOOH  = 5.81 mA cm -2 for MOR at low cell voltage (2.1 V) and remarkable long-term stability). Furthermore, experimental evidences and density functional theory (DFT) calculations demonstrate that the ECR process mainly conducts on NiPc unit with the assistance of NiPor, meanwhile, the MOR prefers NiPor conjugating with NiPc. The two units of NiPc-NiPor COF collaboratively promote the coupled oxidation-reduction reaction. For the first time, this work achieves the rational design of bifunctional COFs for coupled heterogeneous catalysis, which opens a new area for crystalline material catalysts., (© The Author(s) 2023. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

Structural variants of high-nuclearity clusters are extremely important for their modular assembly study and functional expansion, yet the synthesis of such giant structural variants remains a great challenge. Herein, we prepared a lantern-type giant polymolybdate cluster (L-Mo 132 ) containing equal metal nuclearity with the famous Keplerate type Mo 132 (K-Mo 132 ). The skeleton of L-Mo 132 features a rare truncated rhombic triacontrahedron, which is totally different with the truncated icosahedral K-Mo 132 . To the best of our knowledge, this is the first time to observe such structural variants in high-nuclearity cluster built up of more than 100 metal atoms. Scanning transmission electron microscopy reveals that L-Mo 132 has good stability. More importantly, because the pentagonal [Mo 6 O 27 ] n- building blocks in L-Mo 132 are concave instead of convex in the outer face, it contains multiple terminal coordinated water molecules on its outer surface, which make it expose more active metal sites to display superior phenol oxidation performance, which is more higher than that of K-Mo 132 coordinated in M=O bonds on the outer surface., (© 2023 Wiley-VCH GmbH.)

While the difference in catalytic reactivity between mono- and multimetallic sites is often attributed to more than just the number of active sites, still few catalyst model systems have been developed to explore more underlying causal factors. In this work, we have elaborately designed and constructed three stable calix[4]arene (C4A)-functionalized titanium-oxo compounds, Ti-C4A , Ti 4 -C4A , and Ti 16 -C4A , with well-defined crystal structures, increasing nuclearity, and tunable light absorption capacity and energy levels. Among them, Ti-C4A and Ti 16 -C4A can be taken as model catalysts to compare the differences in reactivity between mono- and multimetallic sites. Taking CO 2 photoreduction as the basic catalytic reaction, both compounds can achieve CO 2 -to-HCOO - conversion with high selectivity (close to 100%). Moreover, the catalytic activity of multimetallic Ti 16 -C4A is up to 2265.5 μmol g -1 h -1 , which is at least 12 times higher than that of monometallic Ti-C4A (180.0 μmol g -1 h -1 ), and is the best-performing crystalline cluster-based photocatalyst known to date. Catalytic characterization combined with density functional theory calculations shows that in addition to the advantage of having more metal active sites (for adsorption and activation of more CO 2 molecules), Ti 16 -C4A can effectively reduce the activation energy required for the CO 2 reduction reaction by completing the multiple electron-proton transfer process rapidly with synergistic metal-ligand catalysis, thus exhibiting superior catalytic performance to that of monometallic Ti-C4A . This work provides a crystalline catalyst model system to explore the potential factors underlying the difference in catalytic reactivity between mono- and multimetallic sites.

Plastic mulch, especially polyethylene mulch, is widely used in agricultural production in China, but the microplastics formed by its degradation gradually have accumulated in soil, causing a series of environmental problems. At present, there have been many reports on the environmental biological effects of microplastics in farmland soil, but studies on the effects of microplastics on crop growth, disease occurrence, and rhizosphere soil bacterial communities are still lacking. In the previous study, it was found that 1% high-density polyethylene (HDPE, 500 mesh) could increase the incidence rate of cotton Fusarium wilt (33.3%) and inhibit growth, but this phenomenon was not found after soil sterilization. It was speculated that HDPE could affect the growth and occurrence of Fusarium wilt by regulating the soil microbial community. Therefore, high-throughput sequencing technology, combined with network and FAPROTAX function analysis, were used to investigate the effects of HDPE on the bacterial community structure, interaction network, and soil function in cotton rhizosphere in order to analyze the mechanism of HDPE. NovaSeq sequencing showed that the bacterial community of HDPE-treated cotton rhizosphere soil was composed of 54 phyla and 472 genera; the number of phyla and genera was higher than that in untreated soil. The α and β diversity and ANOSIM/Adonis analyses showed that HDPE significantly reduced the richness of the bacterial community and changed the composition of the community structure. Based on a T -test species difference analysis, HDPE significantly reduced the relative abundance of bacteria with biological control, pollutant degradation, and antifungal drug synthesis (such as Kribbella , Massiliam , Hailiangium , and Ramlibacter ).The change in the bacterial community will lead to the change in soil bacterial function. Further analysis of FAPROTAX function revealed that HDPE weakened some biochemical functions of bacteria in the cotton rhizosphere soil, such as aerobic chemoheterotrophy, fermentation, and nitrate reduction. The correlation network at the genus level showed that HDPE treatment weakened the interaction between rhizosphere bacteria, reduced the number of positive correlation connections, increased the number of negative correlation connections, simplified network structure, and changed the key flora. The above results showed that HDPE could reduce the cotton growth and the occurrence of Fusarium wilt by changing the bacterial community, interaction, and functional metabolism in rhizosphere soil, which can provide guidance for evaluating the ecological risk of polyethylene microplastics and the remediation of contaminated soil.

Rational design of crystalline catalysts with superior light absorption and charge transfer for efficient photoelectrocatalytic (PEC) reaction coupled with energy recovery remains a great challenge. In this work, we elaborately construct three stable titanium-oxo clusters (TOCs, Ti 10 Ac 6 , Ti 10 Fc 8 , and Ti 12 Fc 2 Ac 4 ) modified with a monofunctionalized ligand (9-anthracenecarboxylic acid (Ac) or ferrocenecarboxylic acid (Fc)) and bifunctionalized ligands (Ac and Fc). They have tunable light-harvesting and charge transfer capacities and thus can serve as outstanding crystalline catalysts to achieve efficient PEC overall reaction, that is, the integration of anodic organic pollutant 4-chlorophenol (4-CP) degradation and cathodic wastewater-to-H 2 conversion. These TOCs can all exhibit very high PEC activity and degradation efficiency of 4-CP. Especially, Ti 12 Fc 2 Ac 4 decorated with bifunctionalized ligands exhibits better PEC degradation efficiency (over 99%) and H 2 generation than Ti 10 Ac 6 and Ti 10 Fc 8 modified with a monofunctionalized ligand. The study of the 4-CP degradation pathway and mechanism revealed that such better PEC performance of Ti 12 Fc 2 Ac 4 is probably due to its stronger interactions with the 4-CP molecule and better • OH radical production. This work not only presents the effective combination of organic pollutant degradation and simultaneously H 2 evolution reaction using crystalline coordination clusters as both anodic and cathodic catalyst but also develops a new PEC application for crystalline coordination compounds.

Photo- or electroreduction of carbon dioxide into highly valued products offers a promising strategy to achieve carbon neutrality. Here, a series of polyoxometalate-based metal-organic frameworks (M-POMOFs) were constructed by metalloporphyrins [tetrakis(4-carboxyphenyl)-porphyrin-M (M-TCPPs)] and reductive POM for photo- and electrocatalytic carbon dioxide reductions (PCR and ECR, respectively), and the mysteries between the roles of single metal site and cluster in catalysis were disclosed. Iron-POMOF exhibited an excellent selectivity (97.2%) with high methane production of 922 micromoles per gram in PCR, together with superior Faradaic efficiency for carbon dioxide to carbon monoxide (92.1%) in ECR. The underlying mechanisms were further clarified. Photogenerated electrons transferred from iron-TCPP to the POM cluster for methane generation under irradiation, while the abundant electrons flowed to the center of iron-TCPP for carbon monoxide formation under the applied electric field. The specific multielectron products generated on iron-POMOF through switching driving forces to control electron flow direction between single metal site and cluster catalysis.

Metal-oxo clusters have emerged as advanced proton conductors with well-defined and tunable structures. Nevertheless, the exploitation of metal-oxo clusters with high and stable proton conductivity over a relatively wide temperature range still remains a great challenge. Herein, three sulfate groups decorated zirconium-oxo clusters (Zr 6 , Zr 18 , and Zr 70 ) as proton conductors are reported, which exhibit ultrahigh bulk proton conductivities of 1.71 × 10 -1 , 2.01 × 10 -2 , and 3.73 × 10 -2  S cm -1 under 70 °C and 98% relative humidity (RH), respectively. Remarkably, Zr 6 and Zr 70 with multiple sulfate groups as proton hopping sites show ultralow activation energies of 0.22 and 0.18 eV, respectively, and stable bulk conductivities of >10 -2  S cm -1 between 30 and 70 °C at 98% RH. Moreover, a time-dependent proton conductivity test reveals that the best performing Zr 6 can maintain high proton conductivity up to 15 h with negligible loss at 70 °C and 98% RH, representing one of the best crystalline cluster-based proton conducting materials., (© 2022 Wiley-VCH GmbH.)

Structural exploration and functional application of thorium clusters are still very rare on account of their difficult synthesis caused by the susceptible hydrolysis of thorium element. In this work, we elaborately designed and constructed four stable thorium clusters modified with different functionalized capping ligands, Th 6 -MA , Th 6 -BEN , Th 6 -C8A , and Th 6 -Fcc , which possessed nearly the same hexanuclear thorium-oxo core but different capabilities in light absorption and charge separation. Consequently, for the first time, these new thorium clusters were treated as model catalysts to systematically investigate the light-induced oxidative coupling reaction of benzylamine and thermodriven oxidation of aniline, achieving >90% product selectivity and approximately 100% conversion, respectively. Concurrently, we found that thorium clusters modified by switchable functional ligands can effectively modulate the selectivity and conversion of catalytic reaction products. Moreover, catalytic characterization and density functional theory calculations consistently indicated that these thorium clusters can activate O 2 /H 2 O 2 to generate active intermediates O 2 · - /HOO · and then improved the conversion of amines efficiently. Significantly, this work represents the first report of stable thorium clusters applied to photo/thermotriggered catalytic reactions and puts forward a new design avenue for the construction of more efficient thorium cluster catalysts.

Constructing redox semiconductor heterojunction photocatalysts is the most effective and important means to complete the artificial photosynthetic overall reaction (i.e., coupling CO 2 photoreduction and water photo-oxidation reactions). However, multiphase hybridization essence and inhomogeneous junction distribution in these catalysts extremely limit the diverse design and regulation of the modes of photogenerated charge separation and transfer pathways, which are crucial factors to improve photocatalytic performance. Here, we develop molecular oxidation-reduction (OR) junctions assembled with oxidative cluster (PMo 12 , for water oxidation) and reductive cluster (Ni 5 , for CO 2 reduction) in a direct ( d -OR), alternant ( a -OR), or symmetric ( s -OR) manner, respectively, for artificial photosynthesis. Significantly, the transfer direction and path of photogenerated charges between traditional junctions are obviously reformed and enriched in these well-defined crystalline catalysts with monophase periodic distribution and thus improve the separation efficiency of the electrons and holes. In particular, the charge migration in s -OR shows a periodically and continuously opposite mode. It can inhibit the photogenerated charge recombination more effectively and enhance the photocatalytic performance largely when compared with the traditional heterojunction models. Structural analysis and density functional theory calculations disclose that, through adjusting the spatial arrangement of oxidation and reduction clusters, the energy level and population of the orbitals of these OR junctions can be regulated synchronously to further optimize photocatalytic performance. The establishment of molecular OR junctions is a pioneering important discovery for extremely improving the utilization efficiency of photogenerated charges in the artificial photosynthesis overall reaction.

Hybrid CO 2 electroreduction (HCER) is recognized as an important strategy to improve the total value of redox products and energy conversion efficiency. In this work, a coordination catalyst model system (Ni 8 -TET with active oxidation sites, Ni-TPP with active reduction sites and PCN-601 with redox-active sites) for HCER was established for the first time. Especially, PCN-601 can complete both anodic methanol oxidation and cathodic CO 2 reduction with FE HCOOH and FE CO over 90 %. The performance can be further improved with light irradiation (FE nearly 100 %). DFT calculations reveal that the transfer of electrons from Ni II 8 clusters to metalloporphyrins under electric fields results in the raised oxidizability of Ni 8 clusters and the raised reducibility of metalloporphyrin, which then improves the electrocatalytic performance. This work serves as a well-defined model system and puts forward a new design idea for establishing efficient catalysts for hybrid CO 2 electroreduction., (© 2022 Wiley-VCH GmbH.)

Photocatalytic CO 2 reduction reaction has been developed as an effective strategy to convert CO 2 into reusable chemicals. However, the reduction products of this reaction are often of low utilization value. Herein, we effectively connect photocatalytic CO 2 reduction and amino carbonylation reactions in series to reconvert inexpensive photoreduction product CO into value-added and easily isolated fine chemicals. In this tandem transformation system, we synthesize an efficient photocatalyst, NNU-55-Ni, which is transformed into nanosheets (NNU-55-Ni-NS) in situ to improve the photocatalytic CO 2 -to-CO activity significantly. After that, CO serving as reactant is further reconverted into organic molecules through the coupled carbonylation reactions. Especially in the carbonylation reaction of diethyltoluamide synthesis, CO conversion reaches up to 85%. Meanwhile, this tandem transformation also provides a simple and low-cost method for the 13 C isotopically labeled organic molecules. This work represents an important and feasible pathway for the subsequent separation and application of CO 2 photoreduction product., (© 2022. The Author(s).)

2D nanomaterials with flexibly modifiable surfaces are highly sought after for various applications, especially in room-temperature chemiresistive gas sensing. Here, we have prepared a series of COF 2D nanomaterials (porphyrin-based COF nanosheets (NS)) that enabled highly sensitive and specific-sensing of NO 2 at room temperature. Different from the traditional 2D sensing materials, H 2 -TPCOF was designed with a largely reduced interlayer interaction and predesigned porphyrin rings as modifiable sites on its surfaces for post-metallization. After post-metallization, the metallized M-TPCOF (M=Co and Cu) showed remarkably improved sensing performances. Among them, Co-TPCOF exhibited highly specific sensing toward NO 2 with one of the highest sensitivities of all reported 2D materials and COF materials, with an ultra-low limit-of-detection of 6.8 ppb and fast response/recovery. This work might shed light on designing and preparing a new type of surface-highly-modifiable 2D material for various chemistry applications., (© 2022 Wiley-VCH GmbH.)

Photoreducing carbon dioxide (CO 2 ) into highly valued chemicals or energy products has been recognized as one of the most promising proposals to degrade atmospheric CO 2 concentration and achieve carbon neutrality. Adenine with a photosensitive amino group and aromatic nitrogen atom can strongly interact with CO 2 and has been authenticated for its catalytic activity for the CO 2 photoreduction reaction (CO 2 RR). Herein, two adenine-constructed crystalline biomimetic photocatalysts (Co 2 -AW and Co 2 -AF) were designed and synthesized to achieve CO 2 RR. Between them, Co 2 -AF displayed higher photocatalytic activity (225.8 μmol g -1 h -1 ) for CO 2 -to-HCOOH conversion than that of Co 2 -AW. It was found that the superior charge transfer capacity of the functional ferrocene group in Co 2 -AF is the primary reason to facilitate the photocatalytic performance efficiently. Additionally, this work also demonstrated the great potential of the ferrocene group as an electron donor and mediator in improving the photocatalytic activity of crystalline coordination catalysts.

The exploration of new application forms of covalent organic frameworks (COFs) in Li-S batteries that can overcome drawbacks like low conductivity or high loading when typically applied as sulfur host materials (mostly ≈20 to ≈40 wt % loading in cathode) is desirable to maximize their low-density advantage to obtain lightweight, portable, or high-energy-density devices. Here, we establish that COFs could have implications as microadditives of binders (≈1 wt % in cathode), and a series of anthraquinone-COF based hollow tubes have been prepared as model microadditives. The microadditives can strengthen the basic properties of the binder and spontaneously immobilize and catalytically convert lithium polysulfides, as proved by density functional calculations, thus showing almost doubly enhanced reversible capacity compared with that of the bare electrode., (© 2021 Wiley-VCH GmbH.)

Purposefully designing the well-defined catalysts for the selective electroreduction of CO 2 to C 2 H 4 is an extremely important but challenging work. In this work, three crystalline trinuclear copper clusters (Cu 3 -X, X=Cl - , Br - , NO 3 - ) have been designed, containing three active Cu sites with the identical coordination environment and appropriate spatial distance, delivering high selectivity for the electrocatalytic reduction of CO 2 to C 2 H 4 . The highest faradaic efficiency of Cu 3 -X for CO 2 -to-C 2 H 4 conversion can be adjusted from 31.90 % to 55.01 % by simply replacing the counter anions (NO 3 - , Cl - , Br - ). The DFT calculation results verify that Cu 3 -X can facilitate the C-C coupling of identical *CHO intermediates, subsequently forming molecular symmetrical C 2 H 4 product. This work provides an important molecular model system and a new design perspective for electroreduction of CO 2 to C 2 products with symmetrical molecular structure., (© 2021 Wiley-VCH GmbH.)

The electrochemical CO 2 reduction to high-value-added chemicals is one of the most promising and challenging research in the energy conversion field. An efficient ECR catalyst based on a Cu-based conductive metal-organic framework (Cu-DBC) is dedicated to producing CH 4 with superior activity and selectivity, showing a Faradaic efficiency of CH 4 as high as ~80% and a large current density of -203 mA cm -2 at -0.9 V vs. RHE. The further investigation based on theoretical calculations and experimental results indicates the Cu-DBC with oxygen-coordinated Cu sites exhibits higher selectivity and activity over the other two crystalline ECR catalysts with nitrogen-coordinated Cu sites due to the lower energy barriers of Cu-O 4 sites during ECR process. This work unravels the strong dependence of ECR selectivity on the Cu site coordination environment in crystalline porous catalysts, and provides a platform for constructing highly selective ECR catalysts., (© 2021. The Author(s).)

In the electrochemical CO 2 reduction reaction (CO 2 RR), it is challenging to develop a stable, well-defined catalyst model system that is able to examine the influence of the synergistic effect between adjacent catalytic active sites on the selective generation of C1 or C2 products. We have designed and synthesized a stable crystalline single-chain catalyst model system for electrochemical CO 2 RR, which involves four homomorphic one-dimensional chain-like compounds (Cu-PzH, Cu-PzCl, Cu-PzBr, and Cu-PzI). The main structural difference of these four chains is the substituents of halogen atoms with different electronegativity on the Pz ligands. Consequently, different synergistic effects between bi-copper centers lead to changes in the faradic efficiency (FE CH 4 :FE C 2 H 4 ). This work provides a simple and stable crystalline single-chain model system for systematically studying the influence of coordination microenvironment on catalytically active centers in the CO 2 RR., (© 2021 Wiley-VCH GmbH.)

The design of selective and efficient covalent organic frameworks (COFs) based electrocatalysts with tunable morphology for efficient CO 2 reduction reaction (CO 2 RR) to CH 4 is highly desirable. Here, two kinds of anthraquinone-based COFs (i.e., AAn-COF and OH-AAn-COF) with tunable 1D superstructures (e.g., nanofibers (NF) and hollow tubes (HT)) have been produced via Schiff-base condensation reaction. Interestingly, a rarely reported nanosheet-based self-template mechanism and a nanosheet-crimping mechanism have been demonstrated for the production of COF-based nanofibers and hollow tubes, respectively. Besides, the obtained COF-based superstructures can be post-modified with transition metals for efficient CO 2 RR. Specifically, AAn-COF-Cu (NF) and OH-AAn-COF-Cu (HT) exhibit superior faradaic-efficiency with CH 4 (FE CH4 ) of 77% (-128.1 mA cm -2 , -0.9 V) and 61% (-99.5 mA cm -2 , -1.0 V) in a flow-cell, respectively. Noteworthy, the achieved FE CH4 of AAn-COF-Cu (NF) (77%) the is highest one among reported crystalline COFs. This work provides a general methodology in exploring morphology-controlled COFs for electrocatalytic CO 2 RR., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2021 Science China Press. Published by Elsevier B.V. All rights reserved.)

A series of Li-CO2 battery cathode materials are reported based on metal-organic frameworks with dual-metal sites containing a metalloporphyrin and a metal-coordinated pyrazole. MnTPzP-Mn demonstrates a low voltage hysteresis of 1.05 V at 100 mA g-1 and good stability of 90 cycles at 200 mA g-1. Among them, the Mn-coordinated pyrazole site can promote the effective decomposition of Li2CO3, and the Mn-metalloporphyrin site contributes to the activation of CO2. This is the first example of using a crystalline cathode material with a well-defined structure to reveal natural catalytic sites for CO2 reduction/evolution reactions under aprotic conditions in Li-CO2 batteries.

Metal cluster-based compounds have difficulty finishing the photocatalytic carbon dioxide reduction reaction (CO 2 RR) and water oxidation reaction (WOR) simultaneously because of the big challenge in realizing the coexistence of independently and synergistically reductive and oxidative active sites in one compound. Herein, we elaborately designed and synthesized one kind of crystalline reduction-oxidation ( RO ) cluster-based catalysts connecting reductive { M 3 L 8 (H 2 O) 2 } (M = Zn, Co, and Ni for RO-1 , 2 , 3 respectively) cluster and oxidative {PMo 9 V 7 O 44 } cluster through a single oxygen atom bridge to achieve artificial photosynthesis successfully. These clusters can all photocatalyze CO 2 -to-CO and H 2 O-to-O 2 reactions simultaneously, of which the CO yield of RO-1 is 13.8 μmol/g·h, and the selectivity is nearly 100%. Density functional theory calculations reveal that the concomitantly catalytically reductive and oxidative active sites (for CO 2 RR and WOR, respectively) and the effective electron transfer between the sites in these RO photocatalysts are the key factors to complete the overall photosynthesis., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Cu(I)-based catalysts have proven to play an important role in the formation of specific hydrocarbon products from electrochemical carbon dioxide reduction reaction (CO 2 RR). However, it is difficult to understand the effect of intrinsic cuprophilic interactions inside the Cu(I) catalysts on the electrocatalytic mechanism and performance. Herein, two stable copper(I)-based coordination polymer ( NNU-32 and NNU-33(S) ) catalysts are synthesized and integrated into a CO 2 flow cell electrolyzer, which exhibited very high selectivity for electrocatalytic CO 2 -to-CH 4 conversion due to clearly inherent intramolecular cuprophilic interactions. Substitution of hydroxyl radicals for sulfate radicals during the electrocatalytic process results in an in situ dynamic crystal structure transition from NNU-33(S) to NNU-33(H) , which further strengthens the cuprophilic interactions inside the catalyst structure. Consequently, NNU-33(H) with enhanced cuprophilic interactions shows an outstanding product (CH 4 ) selectivity of 82% at -0.9 V (vs reversible hydrogen electrode, j = 391 mA cm -2 ), which represents the best crystalline catalyst for electrocatalytic CO 2 -to-CH 4 conversion to date. Moreover, the detailed DFT calculations also prove that the cuprophilic interactions can effectively facilitate the electroreduction of CO 2 to CH 4 by decreasing the Gibbs free energy change of potential determining step (*H 2 COOH → *OCH 2 ). Significantly, this work first explored the effect of intrinsic cuprophilic interactions of Cu(I)-based catalysts on the electrocatalytic performance of CO 2 RR and provides an important case study for designing more stable and efficient crystalline catalysts to reduce CO 2 to high-value carbon products.

The sluggish kinetics and unclear mechanism have significantly hindered the development of Li-CO 2 batteries. Here, a Li-CO 2 battery cathode catalyst based on a porphyrin-based covalent organic framework (TTCOF-Mn) with single metal sites is reported to reveal intrinsic catalytic sites of aprotic CO 2 conversion from the molecular level. The battery with TTCOF-Mn exhibits a low overpotential of 1.07 V at 100 mA/g as well as excellent stability at 300 mA/g, which is one of the best Li-CO 2 battery cathode catalysts to date. The unique features of TTCOF-Mn including uniform single-Mn(II)-sites, fast Li + transfer pathways, and high electron transfer efficiency contribute to effective CO 2 reduction and Li 2 CO 3 decomposition in the Li-CO 2 system. Density functional theory calculations reveal that different metalloporphyrin sites lead to different reaction pathways. The single-Mn(II) sites in TTCOF-Mn can activate CO 2 and achieve an efficient four-electron CO 2 conversion pathway. It is the first example to reveal the catalytic active sites and clear reaction pathways in aprotic Li-CO 2 batteries., Competing Interests: The authors declare no competing financial interest., (© 2020 The Authors. Published by American Chemical Society.)

The design of a powerful heterojunction structure and the study of the interfacial charge migration pathway at the atomic level are essential to mitigate the photocorrosion and recombination of electron-hole pairs of CdS in photocatalytic hydrogen evolution (PHE). A temperature-induced self-assembly strategy has been proposed for the syntheses of Prussian blue analogue (PBA)/CdS nanocomposites with beaded structure. The specially designed structure had evenly exposed CdS which can efficiently harvest visible light and inhibit photocorrosion; meanwhile, PBA with a large cavity provided channels for mass transfer and photocatalytic reaction centers. Remarkably, PB-Co/CdS-LT-3 exhibits a PHE rate of 57 228 μmol h -1 g -1 , far exceeding that of CdS or PB-Co and comparable to those of most reported crystalline porous material-based photocatalysts. The high performances are associated with efficient charge migration from CdS to PB-Co through CN-Cd electron bridges, as revealed by the DFT calculations. This work sheds light on the exploration of heterostructure materials in efficient PHE., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Two isostructural MOFs with coordination of different halogen ions (Cl- and Br-), namely NNU-17 and NNU-18, were utilized to reveal the influence of different electron-withdrawing halogen anions on ECR performance. The performance difference between them mainly originates from the different abilities of adsorption and activation of CO2 by halogen ions.

Identification of the real catalytic site in CO 2 reduction reaction (CO 2 RR) is critical for the rational design of catalysts and the understanding of reactive mechanisms. In this study, the catalytic activity of pyridine-containing materials was for the first time structurally demonstrated in CO 2 RR by crystalline supramolecular coordination compounds model system. The system consists of three stable supramolecular coordination compounds (Ni-TPYP, Ni-TPYP-1 and Ni-TPP) with different numbers (4, 2 and 0) of active pyridine groups (i.e. uncoordinated pyridine nitrogen atoms). The electrocatalytic test results show that with the decrease of the number of active pyridine groups, the CO 2 RR performance is gradually reduced, mainly showing the reduction of highest FE CO (99.8%, 83.7% and 25.6%, respectively). The crystallographic, experimental and theoretical evidences prove that the CO 2 RR activity is more likely derived from uncoordinated pyridine nitrogen than the electrocatalytic inert metal nickel in porphyrin center. This work serves as an important case study for the identification of electrocatalytic activity of pyridine-containing materials in CO 2 RR by simple supramolecular model system., (© The Author(s) 2020. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

The synthesis of hollow opening polyhedral cages has always been an attractive but challenging goal, especially with regard to inorganic polyhedral cages. Herein, we present a novel, 240-nuclearity giant polymolybdate cage prepared via hydrothermal synthesis. This cage is composed of 20 tripod-shaped [Mo 6 O 22 (SO 3 )] n - /[Mo 6 O 21 (SO 4 )] n - building blocks with three connected vertices and 30 cubane-type [Mo 4 O 16 ] n - edge building blocks, featuring a rare, nearly regular pentagonal dodecahedron with a large inner cavity (diameter up to 1.8 nm) and 12 opening pentagonal windows. This is the highest nuclearity hollow opening dodecahedral cage reported to date. Importantly, this cage exhibits good stability in solution, as revealed by scanning transmission electron microscopy (STEM), TEM, UV-vis, and Raman spectra. In addition, the bulk sample of this compound exhibits an ultrahigh proton conductivity of 1.03 × 10 -1 S cm -1 at 80 °C and 98% relative humidity, which is the highest among polyoxometalate-based crystalline proton conductors.

A series of stable heterometallic Fe 2 M cluster-based MOFs (NNU-31-M, M=Co, Ni, Zn) photocatalysts are presented. They can achieve the overall conversion of CO 2 and H 2 O into HCOOH and O 2 without the assistance of additional sacrificial agent and photosensitizer. The heterometallic cluster units and photosensitive ligands excited by visible light generate separated electrons and holes. Then, low-valent metal M accepts electrons to reduce CO 2 , and high-valent Fe uses holes to oxidize H 2 O. This is the first MOF photocatalyst system to finish artificial photosynthetic full reaction. It is noted that NNU-31-Zn exhibits the highest HCOOH yield of 26.3 μmol g -1  h -1 (selectivity of ca. 100 %). Furthermore, the DFT calculations based on crystal structures demonstrate the photocatalytic reaction mechanism. This work proposes a new strategy for how to design crystalline photocatalyst to realize artificial photosynthetic overall reaction., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Photocatalytic CO 2 reduction into energy carriers is of utmost importance due to the rising concentrations of CO 2 and the depleting energy resource. However, the highly selective generation of desirable hydrocarbon fuel, such as methane (CH 4 ), from CO 2 remains extremely challenging. Herein, we present two stable polyoxometalate-grafted metalloporphyrin coordination frameworks (POMCFs), which are constructed with reductive Zn-ϵ-Keggin clusters and photosensitive tetrakis(4-carboxylphenyl)porphyrin (H 2 TCPP) linkers, exhibiting high selectivity (>96%) for CH 4 formation in a photocatalytic CO 2 -reduction system. To our knowledge, the high CH 4 selectivity of POMCFs has surpassed all of the reported coordination-framework-based heterogeneous photocatalysts for CO 2 -to-CH 4 conversion. Significantly, the introduction of a Zn-ϵ-keggin cluster with strong reducing ability is the important origin for POMCFs to obtain high photocatalytic selectivity for CH 4 formation, considering that eight Mo V atoms can theoretically donate eight electrons to fulfill the multielectron reduction process of CO 2 -to-CH 4 transformation., (© The Author(s) 2019. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

The energy crisis and environmental pollution have forced scientists to explore alternative energy conversion and storage devices. The anodic reactions of these devices are all oxygen evolution reactions (OER), so the development of efficient OER electrocatalysts is of great significance. At the same time, understanding the reaction mechanism of OER is conducive to the rational design of efficient OER electrocatalysts. In general, catalytic active centers play a direct role in OER performance. In this paper, a series of stable bimetallic metal-organic frameworks (MOFs, named as Fe 3 -Co n -X 2 , n=2, 3 and X=F, Cl, Br) with similar structure were synthesized by changing the halogen coordinated with the cobalt metal active center, aiming to investigate the influence of halogen substitution effect on OER performance. It was found that the OER activity of Fe 3 -Co 3 -F 2 is much better than Fe 3 -Co 2 -Cl 2 and Fe 3 -Co 2 -Br 2 , indicating that the regulation of the electronegativity change of the coordination halogen atom can regulate the coordination electron structure of the metal active center, thereby achieving effective regulation of OER performance., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Over the past 200 years, the most famous and important heteroatom Keggin architecture in polyoxometalates has only been synthesized with Mo, W, V, or Nb. Now, the self-assembly of two phosphate (PO 4 3- )-centered polyoxo-titanium clusters (PTCs) is presented, PTi 16 and PTi 12 , which display classic heteroatom Keggin and its trivacant structures, respectively. Because Ti IV has lower oxidate state and larger ionic radius than Mo VI , W VI , V V , and Nb V , additional Ti IV centres in these PTCs are used to stabilize the resultant heteroatom Keggin structures, as demonstrated by the cooresponding theoretical calculation results. These photoactive PTCs can be utilized as efficient photocatalysts for highly selective CO 2 -to-HCOOH conversion. This new discovery indicates that the classic heteroatom Keggin family can be assembled with Ti, thus opening a research avenue for the development of PTC chemistry., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel polyoxometalate (POM)-based metal-organic framework, TBA 5 [P 2 Mo 16 V Mo 8 VI O 71 (OH) 9 Zn 8 (L) 4 ] ( NNU-29 ), was in situ synthesized and applied into CO 2 photoreduction. The selection of porous material containing a reductive POM cluster is considered to be helpful for CO 2 reduction; meanwhile, a hydrophobic-group-modified organic ligand enables NNU-29 to exhibit good chemical stability and restrains hydrogen generation to some extent. In the photocatalytic CO 2 reduction, the yield of HCOO - reached 35.2 μmol in the aqueous solution with selectivity of 97.9% after 16 h.

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.)

Polyoxometalates (POMs), which possess strong acidity and chemical stability, are promising solid proton conductors and potential candidates for proton exchange membrane fuel cell applications. To investigate how factors such as proton concentration and carrier affect the overall proton conduction, we have synthesized new compounds HImMo 132 (Im, imidazole), HMeImMo 132 , ILMo 132 , and TBAMo 132 with hollow structures and HImPMo 12 with a solid spherelike structure. These crystal models were prepared by encapsulating POM with organic molecules with different proton contents. Among them, the single-crystal sample of the hollow structure HImMo 132 containing more proton sources shows a high proton conductivity of 4.98 × 10 -2 S cm -1 , which was approximately 1 order of magnitude greater than that of the solid cluster HImPMo 12 with the same proton sources and 3 orders of magnitude greater than that of the proton-free organic cation-encapsulated giant ball TBAMo 132 . This study provides a theoretical guidance toward designing and developing new-generation proton conductors and studying their performances at the molecular level.

Normalisation of data, by choosing the appropriate reference genes, is fundamental for obtaining reliable results in quantitative real-time PCR (qPCR). This study evaluated the expression stability of 11 candidate reference genes with different varieties, developmental periods, tissues, and abiotic stresses by using four statistical algorithms: geNorm, NormFinder, BestKeeper, and RefFinder. The results indicated that ubiquitin-conjugating enzyme S (UBC) and ubiquitin-conjugating enzyme E2 (UBC E2) could be used as reference genes for different E. ulmoides varieties and tissues, UBC and histone H4 (HIS4) for different developmental periods, beta-tubulin (TUB) and UBC for cold treatment, ubiquitin extension protein (UBA80) and HIS4 for drought treatment, and ubiquitin-60S ribosomal protein L40 (UBA52) and UBC E2 for salinity treatment. UBC and UBC E2 for the group "Natural growth" and "Total", UBA80 and UBC for the group "Abiotic stresses". To validate the suitability of the selected reference genes in this study, mevalonate kinase (MK), phenylalanine ammonia-lyase (PAL), and 4-coumarate-CoA ligase (4CL) gene expression patterns were analysed. When the most unstable reference genes were used for normalisation, the expression patterns had significant biases compared with the optimum reference gene combinations. These results will be beneficial for more accurate quantification of gene expression levels in E. ulmoides.

The photocatalytic reduction of CO 2 to value-added methane (CH 4 ) has been a promising strategy for sustainable energy development, but it is challenging to trigger this reaction because of its necessary eight-electron transfer process. In this work, an efficient photocatalytic CO 2 -to-CH 4 reduction reaction was achieved for the first time in aqueous solution by using two crystalline heterogeneous catalysts, H{[Na 2 K 4 Mn 4 (PO 4 ) (H 2 O) 4 ]⊂{[Mo 6 O 12 (OH) 3 (HPO 4 ) 3 (PO 4 )] 4 [Mn 6 (H 2 O) 4 ]}·16H 2 O ( NENU-605 ) and H{[Na 6 CoMn 3 (PO 4 )(H 2 O) 4 ]⊂{[Mo 6 O 12 (OH) 3 (HPO 4 ) 3 (PO 4 )] 4 [Co 1.5 Mn 4.5 ]}·21H 2 O ( NENU-606 ). Both compounds have similar host inorganic polyoxometalate (POM) structures constructed with strong reductive {P 4 Mo 6 V } units, homo/hetero transition metal ions (Mn II /Co II Mn II ) and alkali metal ions (K + and/or Na + ). It is noted that the {P 4 Mo 6 V } cluster including the six Mo V atoms served as a multi-electron donor in the case of a photocatalytic reaction, while the transition metal ions functioned as catalytically active sites for adsorbing and activating CO 2 molecules. Additionally, the presence of alkali metal ions was believed to assist in the capture of more CO 2 for the photocatalytic reaction. The synergistic combination of the above-mentioned components in NENU-605 and NENU-606 effectively facilitates the accomplishment of the required eight-electron transfer process for CH 4 evolution. Furthermore, NENU-606 containing hetero-metallic active sites finally exhibited higher CH 4 generation selectivity (85.5%) than NENU-605 (76.6%).

Recently, development of a new type of anode material for lithium-ion batteries that possesses multielectron reaction, sufficient charge transfer, and restricted volume suppression has been considered a huge challenge. Herein, we find a simple hot-pressing method to incorporate polyoxometalate (POM)-based metal-organic frameworks (MOFs) onto three-dimensionally structured carbon cloth (CC), denoted as HP-NENU-5/CC, which immobilizes POMs into the MOFs avoiding the leaching of POMs and employs HP-NENU-5/CC as a flexible, conductive, and porous anode material. The HP-NENU-5/CC anode materials show outstanding electrochemical performance, exhibiting high reversible capacity (1723 mAh g -1 at 200 mA g -1 ), high rate capability (1072 mAh g -1 at 1000 mA g -1 ), and superior cycling stability (1072 mAh g -1 at 1000 mA g -1 after 400 cycles). Most importantly, the performance of HP-NENU-5/CC is the best among those of all reported POMs and MOF-based materials. In addition, we perform a comparative study for active materials coated on a two-dimensional current collector and CC, and our experimental results and analysis prove that the active material coated on CC does enhance the electrochemical performance.

Despite wide applications of bimetallic electrocatalysis in oxygen evolution reaction (OER) owing to their superior performance, the origin of the improved performance remains elusive. The underlying mechanism was explored by designing and synthesizing a series of stable metal-organic frameworks (MOFs: NNU-21-24) based on trinuclear metal carboxylate clusters and tridentate carboxylate ligands. Among the examined stable MOFs, NNU-23 exhibits the best OER performance; particularly, compared with monometallic MOFs, all the bimetallic MOFs display improved OER activity. DFT calculations and experimental results demonstrate that introduction of the second metal atom can improve the activity of the original atom. The proposed model of bimetallic electrocatalysts affecting their OER performance can facilitate design of efficient bimetallic catalysts for energy storage and conversion, and investigation of the related catalytic mechanisms., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)