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An electrochemical sensor based on porous aromatic cages was reported, which can achieve chiral sensing of DOPA enantiomers. The prepared sensor can achieve a recognition efficiency of up to 2.6 for DOPA enantiomers. The enhanced recognition efficiency could be attributed to the cooperation of intermolecular interactions, and the efficient charge transfer process. [ABSTRACT FROM AUTHOR]

The development of electrocatalysts that convert CO2 and N2 in flue gas to directly usable urea does not only explore the hidden value of exhaust gas but also alleviates the global environmental issues caused by excessive CO2 emissions; yet, related research studies are still in their infancy. Herein, multi-porous Cu–W18O49@ZIF-8, composed of ultra-small nanosized ZIF-8 on Cu-doped W18O49 nanowires, was fabricated as a urea-generation electrocatalyst in flue gas. It exhibits an appealing Faraday efficiency of urea up to 16.1% at −0.9 V (vs. RHE) and an outstanding yield of 1.33 mmol g−1 h−1 at −1.0 V (vs. RHE) under the flue gas atmosphere. The catalytic performance was maintained for a wide range of N2 : CO2 ratios. Theoretical calculations indicate that the doped copper regulates the electron density around the adjacent W–W, which facilitates N2 adsorption, partly suppresses the HER side reaction, and decreases the ΔG of the following multi-step hydrogenation after *CO insertion until urea production. [ABSTRACT FROM AUTHOR]

Over the past few decades, the critical role played by cellular contractility associated mechanotransduction in the regulation of cell functions has been revealed. In this case, numerous biomaterials have been chemically or structurally designed to manipulate cell behaviors through the regulation of cellular contractility. In particular, adhesive proteins including fibronectin, poly- L -lysine and collagen type I have been widely applied in various biomaterials to improve cell adhesion. Therefore, clarifying the effects of adhesive proteins on cellular contractility has been valuable for the development of biomaterial design. In this study, reference-free traction force microscopy with a well-organized microdot array was designed and prepared to investigate the relationship between adhesive proteins, cellular contractility, and mechanotransduction. The results showed that fibronectin and collagen type I were able to promote the assembly of focal adhesions and further enhance cellular contraction and YAP activity. In contrast, although poly- L -lysine supported cell spreading and elongation, it was inefficient at inducing cell contractility and activating YAP. Additionally, compared with cellular morphogenesis, cellular contraction was essential for YAP activation. [ABSTRACT FROM AUTHOR]

Halide perovskite nanocrystals are innovative luminescent materials for fluorescent probes with high quantum yield and narrow emission bandwidth. However, the limited stability, single-signal response, and separation challenges obstruct their widespread use in water ion detection. Herein, a ratiometric fluorescence sensor based on terbium alginate gel beads (green fluorescent, namely Tb-AG) embedded with powdered CsPbI3@Pb-MOF (red fluorescent) was prepared for fluorescent determination and adsorption of Fe3+. Pb-MOF's protection notably enhances the water stability of CsPbI3, while the energy transfer between CsPbI3@Pb-MOF and Tb3+ elevates the optical performance of CsPbI3@Pb-MOF@Tb-AG. Significantly, Fe3+ markedly suppresses CsPbI3@Pb-MOF red fluorescence at 647 nm, while not noticeably affecting Tb-AG green emission at 528 nm. The sensor exhibited a strong linear response to Fe3+ concentrations ranging from 0 to 90 μM, with a detection limit of 0.44 μM and high selectivity. The CsPbI3@Pb-MOF@Tb-AG-based sensor has been effectively validated through its successful use in detecting Fe3+ in tap and river water samples. Furthermore, CsPbI3@Pb-MOF@Tb-AG demonstrates a notable adsorption capacity of 325.4 mg g−1 Fe3+. Finally, the mechanism of Fe3+ detection and adsorption was determined. [ABSTRACT FROM AUTHOR]

Non-invasive cancer therapies, especially those based on reactive oxygen species, including photodynamic therapy (PDT), have gained much interest. As emerging photodynamic nanocarriers, metal–organic frameworks (MOFs) based on porphyrin can release reactive oxygen species (ROS) to destroy cancer cells. However, due to the inefficient production of ROS by photosensitizers and the over-expression of glutathione (GSH) in the tumor microenvironment (TME), their therapeutic effect is not satisfactory. Therefore, herein, we developed a multi-functional nanoparticle, HN@Cu-MOF, to enhance the efficacy of PDT. We combined chemical dynamic therapy (CDT) and nitric oxide (NO) therapy by initiating sensitization to PDT and cell apoptosis in the treatment of tumors. The Cu2+-doped MOF reacted with GSH to form Cu+, exhibiting a strong CDT ability to generate hydroxyl radicals (˙OH). The Cu-MOF was coated with HN, which is hyaluronic acid (HA) modified by a nitric oxide donor. HN can target tumor cells over-expressing the CD44 receptor and consume GSH in the cells to release NO. Both cell experiments and in vivo experiments showed an excellent tumor inhibitory effect upon the treatment. Overall, the HN@Cu-MOF nanoparticle-integrated NO gas therapy and CDT with PDT led to a significant enhancement in GSH consumption and a remarkable elevation in ROS production. [ABSTRACT FROM AUTHOR]

Hard-Soft Acid-Base (HSAB) principle plays an important guiding role in the design and synthesis of novel clusters and coordination compounds, in which "soft acids prefer to react with soft bases, while hard acids have an affinity for hard bases". Based on HSAB principle, four Ag/Ti heterometallic clusters, including Ag2Ti10, Ag2Ti11 with "Ti-encapsulated Ag" configurations, and two "Ag-encapsulated Ti" structures Ag2Ti2 and Ag2Ti12, were synthesized under solvothermal conditions. In addition, Ag2Ti12 exhibited an efficient and stable catalytic activity for sulfide oxidation. This work provides not only a new structural model for the modulation of the catalytic oxidative desulfurization properties of Ag/Ti heterometallic clusters but also a new insight of the utilization of phosphine-containing ligands to regulate the structure of Ag/Ti heterometallic clusters. [ABSTRACT FROM AUTHOR]

The photocatalytic degradation of tetracycline hydrochloride (TCH) under high salinity poses a significant challenge due to the inhibitory effect of coexisting ions on reactive oxygen species in wastewater. Herein, a series of hierarchically porous Z-scheme CsPbBr3@HZIF-8 heterojunctions were synthesized by a sequential deposition method. Benefiting from the stable hierarchical pore structure of HZIF-8 and the excellent optoelectronic properties of CsPbBr3, the hierarchical pore Z-scheme heterojunction CsPbBr3@HZIF-8 not only facilitates the mass transfer and enrichment of pollutants but also accelerates the transfer of carriers between HZIF-8 and CsPbBr3, leading to enhanced generation of reactive oxygen species. Moreover, CsPbBr3 serves as a photosensitizer for energy transfer, generating singlet oxygen (1O2) with higher resistance to ion interference. As a result, the 4%-CsPbBr3@HZIF-8 achieved the highest visible light degradation efficiency of TCH (94% in 40 min), surpassing those of most reported CsPbBr3-based photocatalysts. The catalytic system consistently degrades contaminants in deionized water, high ion concentrations, and real water matrices. The photocatalytic reaction mechanisms, involving charge carrier transfer, reactive species generation, and TCH degradation intermediate products, are thoroughly investigated. [ABSTRACT FROM AUTHOR]

Designing low-cost, stable and earth-abundant transition metal-based electrocatalysts to replace Pt-based catalysts is of significant importance for green and sustainable energy technologies. W-based carbon materials are crucial hydrogen evolution reaction (HER) electrocatalysts, but the synthesis and stability of such materials still face great challenges that hamper the development of such applications. Herein, WN/W2C porous composites with a carbon shell (WN/W2C@PC) were prepared by forming a pyrolytic polyoxometalate-intercalated layered double hydroxide (LDH) with glucose and NH4Cl as templates. The composites possess a high specific surface area of 633.74 m2 g−1, which offers more active sites and promotes the HER performance. Compared with most non-precious metal-based electrocatalysts, WN/W2C@PC undergoes an outstanding HER with a low overpotential of 121.3 mV and 91 mV at 10 mA cm−2 under 0.5 M H2SO4 and 1 M KOH, respectively, and exhibits robust long-term stability. This work provides novel insights for the rational design and preparation of efficient non-precious metal-based HER electrocatalysts. [ABSTRACT FROM AUTHOR]

The design and synthesis of high-nuclear polyoxometalates (POMs) constructed from pentagonal molecular building blocks (MBBs) are attractive and challenging. Herein, three new high-nuclear polyoxovanadates, including {V20W2P20} (1), {V18W4P14} (2), and {V26W6P16} (3), have been successfully synthesized under solvothermal conditions. All these structures are assembled from pentagonal MBB {WV5(PhPO3)5} with different configurations. Compound 1 exhibits efficient, stable, and versatile catalytic activity for sulfide oxidation. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) photosensitizers with rapid reactive oxygen species (ROS) production ability are in great demand owing to their promising performance toward boosting photodynamic therapy (PDT) and deep-tissue imaging, but molecular design guidelines for efficient photosensitizers are rarely elucidated. Herein, three AIEgens named DBP, TBP, and TBP-SO3 are designed and synthesized by precise donor–acceptor (D–A) molecular engineering to deeply understand the structure–property–application relationships. All the compounds exhibit AIE characteristics with strong long-wavelength emission in the aggregated state and are capable of efficiently producing ROS under white light irradiation. By controlling the ability of the D–A units, TBP-SO3 realizes NIR emission and more rapid ROS generation ability due to the promoted intersystem crossing processes compared with those of DBP and TBP. In addition, NIR-emitting TBP-SO3 is capable of specific endoplasmic reticulum targeting and excellent PDT treatment ability of cancer cells and bacteria. This successful example of molecular engineering paves a valuable way for developing advanced PSs with AIE properties, efficient ROS generation ability, and intense emission for fluorescence imaging PDT. [ABSTRACT FROM AUTHOR]

Ultralong organic phosphorescent (UOP) luminogens are of great practical importance in the field of optoelectronics, however, it remains a significant challenge to construct materials with high phosphorescent yields (Φph) and long lifetimes simultaneously. We herein present a feasible molecular engineering strategy to boost the Φph and lifetime via a synergistic heavy-atom effect and methylation approach used to adjust the intrinsic photophysical processes and solid packing. As expected, efficient UOP with an enhanced Φph of 11.1% and an improved lifetime of 391 ms is obtained for BrMOPP consisting of one methyl moiety and bromine atom in the S,S-dioxide phenothiazine skeleton, which is much better than that of reference luminogen without functional units (0.5%, 185 ms). Dense network packing formed through multiple intramolecular interactions along with a, b, and c axis directions provides the rigid molecular alignment in the three-dimensional framework, suppressing the nonradiative relaxation pathway. Combining with the efficient intersystem crossing induced by the bromine atom, the resulting phosphors with excellent Φph and long lifetime are achieved, and are successfully applied to anti-counterfeiting and data encryption. This study will provide a reasonable approach for further optimizing the UOP performance from the molecular level. [ABSTRACT FROM AUTHOR]

The synthesis of chiral lanthanide metal clusters has always attracted the interest of researchers. Herein, a pair of chlorine anion-induced axially chiral tetranuclear europium clusters, namely, [Eu4Cl2 (R-BNP) 8(EtOH)8(H2O)4]Cl2·7H2O (R-4) and [Eu4Cl2 (S-BNP) 8(EtOH)8(H2O)4]Cl2·7H2O (S-4), are synthesized under solvothermal conditions. In the structure, a unique tetranuclear europium cluster is encapsulated by eight chiral binaphthol phosphate ligands. The chirality between enantiomers is confirmed by single-crystal X-ray diffraction and circular dichroism. Furthermore, since R-4 and S-4 can fluoresce red at room temperature, they can be used for the detection of Fe3+ ions and nitro explosives. In addition, cycling tests of the sensing have shown that R-4 and S-4 can be used as excellent fluorescent sensors. [ABSTRACT FROM AUTHOR]

2,4,6-Trinitrophenol (TNP) is a highly explosive and toxic nitroaromatic compound. The selective detection of TNP is crucial for human safety and the social environment. As a novel multifunctional material, coordination polymers are considered to be a promising sensing platform for TNP detection. Herein, a novel luminescent N-rich CP, [In(HTzPTpy)Cl2] (CUST-801) is successfully designed for TNP detection. X-ray single-crystal diffraction results show that In atoms are connected by HTzPTpy ligands to form a 1D zig-zag chain. CUST-801 exhibits bright green fluorescence in the aggregated state and has a high water stability for up to 14 days. Benefitting from these properties, CUST-801 is an outstanding fluoroprobe to quantitatively detect related nitroaromatic compounds, such as 2,4-dinitrotoluene, p-nitrotoluene, 1,3-dinitrobenzene, nitrobenzene, and TNP, by fluorescence quenching. In particular, CUST-801 can be used as a selective and sensitive promising sensor to detect TNP. The calculated quenching constant of CUST-801 towards TNP is 8.95 × 104 M−1, and the detection limit is 0.3 ppm in aqueous media. Simultaneously, CUST-801 possesses excellent reusability. In addition, DFT and UV-Vis absorption proved that the quenching phenomenon could be primarily ascribed to electron transfer and the resonance energy transfer effect between CUST-801 and TNP. [ABSTRACT FROM AUTHOR]

Two new zirconium-based heterometal–organic frameworks, Zr3CP3–Mn (1) and Zr3CP3–Ni (2), constructed from [Cp3Zr3(μ3-O)(μ2-OH)3(IN)3] secondary building units and transition metal cations, were successfully synthesized through a one-pot method. Single-crystal X-ray diffraction analysis shows that both 1 and 2 have one-dimensional chain structures, in which [Cp3Zr3(μ3-O)(μ2-OH)3(IN)3] SBUs are connected by Mn and Ni ions. Furthermore, photoreduction of CO2 under visible light irradiation reveals that 1 and 2 have good catalytic activities to reduce CO2 into carbon monoxide and hydrogen. The CO yields of 1 and 2 were 9.30 and 5.21 mmol g−1 h−1 under one hour irradiation at 293 K, respectively. In addition, the inherent photocatalytic mechanism was studied through photochemical and electrochemical measurements. This work provides a valuable perspective for the design and synthesis of simple, low-cost MOF catalysts for photoreduction of CO2. [ABSTRACT FROM AUTHOR]

Hemoperfusion has become the third-generation treatment strategy for patients suffering from hyperbilirubinemia, but adsorbents used for bilirubin removal mostly face intractable problems, such as unsatisfactory adsorption performance and poor hemocompatibility. Metal–organic frameworks (MOFs) are promising adsorbents for hemoperfusion due to their high specific surface areas and easily modified organic ligands. However, their microporous properties and separation have hampered their application. Here, a novel hierarchical core–shell nanoplatform (named Double-PEG) with tailored binding sites and pore sizes based on Fe3O4@C and Uio66-NH2 was constructed. Notably, Double-PEG showed excellent bilirubin uptake of up to 1738.30 mg g−1 and maintained excellent bilirubin removal efficiency in simulated biological solutions. A study on the adsorption mechanism showed that the adsorption of Double-PEG towards bilirubin tended to be chemical adsorption and in accordance with the Langmuir model. Besides, the good separability, recyclability, cytotoxicity and hemocompatibility of Double-PEG show great potential in hemoperfusion therapy. The finding of this study may provide a novel insight into the application of MOF materials in the field of hemoperfusion. [ABSTRACT FROM AUTHOR]

Herein, we design and prepare a dual-emitting lanthanide metal–organic framework (Eu0.07Gd0.03-MOF) based on functionalized ligands, which can be developed as a ratiometric sensor. This self-calibrated material not only displays high water stability but also offers a highly sensitive and color change detection of Fe3+ and ascorbic acid at a low limit of detection. Moreover, water stability surveys for Eu0.07Gd0.03-MOF indicate that it maintains structural stability and displays at least 90.4% and 87.5% fluorescence intensity after storage in water for 28 days in water at 70 °C for 6 days, as well as in acidic-basic solutions of broad pH range (3–11) for four days. More importantly, the low concentration range of Fe3+ and ascorbic acid can be estimated by the ratios of ligand-based emission as an internal reference and Eu3+-based emission as the indicator, thus yielding a visually discernible "color-change-recover" effect. [ABSTRACT FROM AUTHOR]

We synthesized a novel MOF with an sqc1575 topology as an ideal host matrix that exhibits luminescence energy transfer with polycyclic aromatic hydrocarbons (PAHs). What's more, the PAHs@MOF composites display an interesting quenching behavior in the presence of the electron donor triethanolamine (TEOA). We report for the first time that the well-defined porosity of a luminescent MOF enables it to serve as a host matrix for encapsulating chromophoric PAH molecules to modulate luminescence properties, and further exploit its reductive quenching properties by using a photocatalytic sacrificial electron donor. [ABSTRACT FROM AUTHOR]

The development of metal complexes for optoelectronic applications is a fertile area of research. In contrast to the rigorous development of mononuclear metal complexes, dinuclear species have been less well studied and their fundamental chemistry and applications are under-explored. However, dinuclear species present special properties and functions compared with mononuclear species as a consequence of tuning the bridging ligands, the cyclometalated ligands or the two metal centers. More recently, dinuclear species have enabled important breakthroughs in the fields of OLEDs, photocatalytic water splitting and CO2 reduction, DSPEC, chemosensors, biosensors, PDT, smart materials and so on. Here we present an overview of recent developments of dinuclear metal complexes, their multifunctional properties and their various applications. The relationship between structure and property of dinuclear species and important factors which influence device performance are discussed. Finally, we illustrate some challenges and opportunities for future research into dinuclear metal complexes. This review aims to provide an up-to-date summary and outlook of functional dinuclear metal complexes and to stimulate more researchers to contribute to this exciting interdisciplinary field. [ABSTRACT FROM AUTHOR]

A novel Br-regulated "Transition Metal Active-site Anchoring and Exposure" (TMAAE) strategy is reported, for the first time, to fabricate a hierarchical porous Co/N-doped bio-carbon bifunctional electrocatalyst (CoTBrPP@bio-C) for an all-pH ORR and HER by using a simple one-pot co-pyrolysis over a mushroom (MR) template with adsorbed Br-substituted porphyrinato cobalt (CoTBrPP). Introduction of CoTBrPP onto the MR template not only leads to a larger specific area of 604 m2 g−1 in CoTBrPP@bio-C relative to that of CoTPP@bio-C (CoTPP = Br-free CoTBrPP), 98 m2 g−1, but more importantly also regulates the oriented distribution of pores precisely which promotes effective exposure of multiple active sites depending on the departure of Br-species attached to the Co–N4 macrocycle periphery. Impressively, CoTBrPP@bio-C with a Co loading down to 0.77 at% exhibits higher all-pH ORR and HER performance compared to CoTPP@bio-C with a Co loading of 3.5 at%. An efficient TMAAE makes CoTBrPP@bio-C possess higher onset and half-wave potentials of 0.93 and 0.85 V for the ORR, and a smaller Tafel slope of 80 mV dec−1 for the HER in an alkaline medium. CoTBrPP@bio-C also had a superior all-pH long-term stability and outstanding methanol tolerance, surpassing commercial Pt/C and most non-precious-metal catalysts reported to date. Furthermore, Zn–air batteries assembled with CoTBrPP@bio-C exhibited a higher peak power density of 100 mW cm−2 and excellent durability than Pt/C. [ABSTRACT FROM AUTHOR]

CsPbBr3 is widely used in solar cells and LEDs for its excellent photoelectric properties that are also attractive for CO2 photoreduction, but it is less used in the photocatalytic reduction of CO2 mainly owing to its limited charge separation efficiency. To alleviate this issue, herein, all-inorganic orthorhombic CsPbBr3 was combined with graphitic carbon nitride (g-C3N4) and the resultant composite (CsPbBr3@g-C3N4) showed enhanced activity in CO2 photoreduction. Under the irradiation of AM1.5 filter for 12 h, CO2 was converted into CH4 and CO with high selectivity to methane (91%) and the total amount of gaseous products up to ∼300 μmol g−1. This reactivity is 6-fold and 4-fold higher than that of pure g-C3N4 and CsPbBr3, respectively. CsPbBr3@g-C3N4 also shows excellent catalytic activity at low concentrations of CO2. Studies of energy band level and steady-state and transient photoluminescence spectroscopy indicated that the incorporation of CsPbBr3 and g-C3N4 increases charge separation, which may result in sharply enhanced catalytic efficiency. This study has provided opportunities for the combination of CsPbBr3 and other semiconductor catalysts for the photocatalytic reduction of CO2. [ABSTRACT FROM AUTHOR]

Newfangled frangipani-like [MV5O6(μ3-O)5(SO4)(COO)5] (M = Nb/W) polyanions served as 5-connected molecular building blocks (MBBs) that simultaneously assembled with 4-connected [V5O9Cl] MBBs and tricarboxylate ligands (H3BTC) to form two new polyoxovanadate-based metal–organic polyhedra {[MV5O6(μ3-O)5(SO4)]4[V5O9Cl]4(BTC)12} with undiscovered "near-miss Johnson solid" geometry. Moreover, the variable-temperature magnetic susceptibilities were investigated. [ABSTRACT FROM AUTHOR]

Rechargeable lithium–sulfur (Li–S) batteries are regarded as a promising option for electrochemical energy storage systems. However, one of the key issues hindering their practical application is lithium polysulfide (LiPS) shuttling, which results in severe capacity decay and self-discharge. Separator-decoration with oxides has been demonstrated to be an effective strategy and has attracted widespread attention. But there has been no report about intergrown multi-phase composite oxides for separator modification. Herein, spent layered cathode (LiNi0.5Co0.2Mn0.3O2) derived layered–spinel–rocksalt intergrown oxides were firstly introduced and investigated. Unexpectedly superior performance was obtained with high reversible capacity and outstanding stability, which could be contributed by the entrapping and catalysis of LiPSs. The Li–S batteries with the spent multi-phase composite LiNi0.5Co0.2Mn0.3O2 show a low fading rate of 0.053% per cycle over 550 cycles at 1C rate, and high discharge capacities of 976.1, 916.7, 865.2, and 795.1 mA h g−1 at 0.5, 1, 2, and 3C rates, respectively. DFT calculation demonstrated that the spinel and rock-salt phases can provide more energetic reaction sites to strongly adsorb the LiPSs and accelerate the catalyzed conversion of LiPSs to Li2S/Li2S2. Moreover, our systematic experimental and theoretical investigation produced intriguing results, indicating that there is a synergistic effect between the spinel, rock-salt and layered phases. This study not only provides a high-value application of spent LiNi0.5Co0.2Mn0.3O2 but also demonstrates the potential of multi-phase composites to boost the performance of Li–S batteries. [ABSTRACT FROM AUTHOR]

Micro- and nano-structured substrates have been widely used in the biomedical engineering field. Their precise control of cell morphology makes them promising for investigating various cell behaviors. However, regulation of cell functions using micro–nano hybrid patterns is rarely achieved. Since the cell microenvironment in vivo has complex micro- and nano-structures, it is desirable to use micro–nano hybrid patterns to mimic the microenvironment to control cell morphology and disclose its influence on stem cell differentiation. In this study, poly(vinyl alcohol) (PVA) micro-stripes with different spacings (50 μm, 100 μm and 200 μm) were constructed on polystyrene (PS) nano-grooves to prepare micro–nano hybrid patterns where the direction of the PVA micro-stripes and PS nano-grooves was parallel or orthogonal. Human bone marrow-derived mesenchymal stem cells (hMSCs) cultured on the micro–nano hybrid patterns showed a different cell alignment and elongation dependent on the PVA micro-stripe spacing and orientation of the PS nano-grooves. Comparison of the influence of cell alignment and aspect ratio on differentiation of hMSCs indicated that myogenic differentiation was predominantly regulated by cell alignment and osteogenic differentiation by cell elongation, while adipogenic differentiation was regulated neither by cell alignment nor by cell elongation. [ABSTRACT FROM AUTHOR]

To explore cost-efficient, highly active and robust bifunctional electrocatalysts for overall water splitting, both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), is of much significance for renewable-energy systems but remains challenging as well. Herein, we report two multicomponent heterostructures as efficient bifunctional electrocatalysts, Co2P/Mo2C/Mo3Co3C and Ni/Ni2P/Mo2C nanoparticles encapsulated in porous graphene shells (termed Co2P/Mo2C/Mo3Co3C@C and Ni/Ni2P/Mo2C@C). Two bimetallic MOFs (CoMo-MOF and NiMo-MOF) with ordered heterogeneity were used as precursors to synthesize Co2P/Mo2C/Mo3Co3C@C and Ni/Ni2P/Mo2C@Cvia a facile and versatile two-step method and a direct carbonization process followed by phosphorization. The resultant catalysts manifest superior HER performance with low overpotentials of 154 and 183 mV delivering a current density of 10 mA cm−2 in acidic media. More importantly, both Co2P/Mo2C/Mo3Co3C@C and Ni/Ni2P/Mo2C@C exhibit favorable HER and OER activity under alkaline conditions. Remarkably, Co2P/Mo2C/Mo3Co3C@C affords overpotentials of 182 mV and 362 mV at 10 mA cm−2 for the HER and OER. Moreover, the two catalysts present good stability in both acidic and basic electrolytes. The synergistic effect of the multicomponent electrochemically active species and the uniform distribution, mesoporous structures and carbon coating are beneficial for the charge transfer during the catalytic process, which results in excellent performance, comparable to many reported nonprecious electrocatalysts. Furthermore, Co2P/Mo2C/Mo3Co3C@C catalysts were exploited as both the anode and cathode in a home-made electrolyser with alkaline electrolyte, which can afford 10 mA cm−2 at a cell voltage of 1.74 V. [ABSTRACT FROM AUTHOR]

Increasing global challenges including climate warming and energy shortage have stimulated worldwide explorations for efficient materials for applications in the capture of CO2 and its conversion to chemicals. In this study, a novel pillared-layer porous metal–organic framework (Co6–MOF) with high nuclearity CoII clusters has been synthesized. This material exhibited a CO2 adsorption capacity of up to 55.24 cm3 g−1 and 38.17 cm3 g−1 at 273 K and 298 K, respectively. In a heterogeneous photocatalytic system of CO2 reduction, this material, co-operated with a ruthenium-based photosensitizer, can efficiently realize CO2 to CO conversion. Under visible-light irradiation for 3 hours, 39.36 μmol CO and 28.13 μmol H2 were obtained. This result is higher than those of most of the reported MOF materials under similar conditions and to the best of our knowledge, this is the first example of a high nuclear MOF used in CO2 reduction. The rooted reasons behind the high reactivity were studied through theoretical calculation studies. The results showed that electrons on reduced [Ru(bpy)3]Cl2·6H2O (bpy = 4,4′-bipyridine) could transfer to the Co6–MOF and the adsorbed CO2 molecule on the charged Co6–MOF could be activated more facilely. This work not only clarifies the reasons for high efficiency of the CO2 photoreduction system but also points out to us the direction for designing more effective MOF materials as photocatalysts for artificial CO2 photoreduction. [ABSTRACT FROM AUTHOR]

Alkyl chain engineering has been employed to tune the physicochemical properties of conjugated polymers. Usually, several building blocks with different alkyl chains need to be synthesized in multiple steps, which is synthetically costly. Also, it is challenging to systematically tune the alkyl chains to enhance device performances due to the complex morphological characteristics of the conjugated polymers and the effects of molecular weight and purity. Here we designed and synthesized a series of conjugated polymers with similar molecular weights through random polymerization of BDT building blocks with two TT building blocks possessing different alkyl chains. Upon simply altering the molecular ratio of two TT units, the physicochemical characteristics, solid state packing, and photovoltaic properties of the conjugated polymers were systematically tuned. As a result, a conjugated polymer that can pair with both fullerene (PC71BM) and non-fullerene (ITIC-Th) acceptors to generate high power conversion efficiencies (10.3% and 9.1%, respectively) was achieved. This contribution provides a novel strategy for designing high performance conjugated polymers. [ABSTRACT FROM AUTHOR]

In this study, we synthesized a low-cost electrocatalyst, Ni/Mo2C nanoparticles coated with graphene shells (denoted as NiMo2C@C), via a facile carburization process of porous bimetallic metal–organic frameworks (NiMo-MOF). This is the first example of a Ni and Mo2C nanocomposite derived from a bimetallic MOF that demonstrates excellent electrocatalytic activity and remarkable durability as long as 10 h under acidic and basic conditions. The overpotentials are 169 mV and 181 mV to reach the current density of 10 mA cm−2, respectively. The favorable performance can be ascribed to the synergistic effect between Mo2C and Ni as well as the homogeneous distribution, graphene coating and mesoporous structure which is in favor of the charge transfer in the HER. This work may provide some guidelines for fabricating nanostructured hybrids composed of versatile transition metal carbides and graphene with high performance and stability in different media based on designed MOFs. [ABSTRACT FROM AUTHOR]

We utilised the rich coordination character of Wells–Dawson polyoxometalates (POMs) to explore the higher-level helical conformation of hybrids. Herein, two compounds, [Ag26(Trz)16(OH)4][P2W18O62] (1) and Na[Ag16(Trz)9(H2O)4][P2W18O62]·H2O (2) (Trz = 1,2,3 triazole), with multi-fold meso-helices were successfully isolated. Both 1 and 2 displayed two different types of four-fold meso-helices, which are composed of POMs and organic–metal subunits. The interesting thing is that the four-fold helixes of 2 sequentially evolve into the most complex eight-fold meso-helices by sharing the building blocks. In addition, the multi-chelate patterns of Wells–Dawson POMs in 2 represent the highest coordination numbers to date, which dominates the evolution from four-fold to eight-fold meso-helices. For the first time, the Wells–Dawson POMs-based hybrids 1 and 2 have been used as anode materials in lithium-ion batteries (LIBs). The initial specific capacities of 1077 mA h g−1 for 1 and 1094 mA h g−1 for 2 were much higher than those of (NBu4)6[P2W18O62] and commercial graphite as reference anodes at a current density of 100 mA cm−2. Also, both of them showed stable performance after 100 cycles. [ABSTRACT FROM AUTHOR]

Encapsulation of single mammalian cells with biocompatible and protective materials has important applications in biomedical and single-cell biology research. To date, single mammalian cells have generally been encapsulated by physical approaches including hydrophobic and electrostatic interactions. However, the cytotoxicity of the used materials, short sustained period, and especially loose structure of the encapsulation layer have limited the application of the encapsulated cells. Here, we show a novel strategy based on in situ polymerization for encapsulation of single mammalian cells with a network structure of the polymeric shell under mild conditions. Using the present strategy, the encapsulated mammalian cells, HeLa cells, hMSCs, and BACs showed high viability. Furthermore, the encapsulation shell was able to prevent the penetration of macro-external entities, while maintaining the free exchange of smaller molecules. This work provides a new and versatile method for single mammalian cell encapsulation. [ABSTRACT FROM AUTHOR]

An organic chromophore H4tcbpe-F was synthesized and immobilized into metal–organic frameworks along with two bipyridine derivatives as co-ligands to generate two strongly luminescent materials [Zn2(tcbpe-F)(4,4′-bpy)·xDMA] (1) and [Zn2(tcbpe-F)(bpee)·xDMA] (2) [4,4′-bpy = 4,4′-bipyridine, bpee = 4,4′-bipyridyl-ethylene, tcbpe-F = 4′,4′′′,4′′′′′,4′′′′′′′-(ethene-1,1,2,2-tetrayl)tetrakis(3-fluoro-[1,1′-biphenyl]-4-carboxylic acid), DMA = N,N-dimethylacetamide]. Compounds 1 and 2 are isoreticular and feature a 2-fold interpenetrated three-dimensional porous structure. Both compounds give green-yellow emission under blue light excitation. Compound 1 has a high internal quantum yield of ∼51% when excited at 455 nm and shows selective luminescence signal change (e.g. emission energy and/or intensity) towards different solvents, including both aromatic and nonaromatic volatile organic species. These properties make it potentially useful as a lighting phosphor and a chemical sensor. [ABSTRACT FROM AUTHOR]

In our efforts to explore promising substitutes for Pt-based electrocatalysts for the hydrogen evolution reaction (HER), a new type of molybdenum carbide nanoparticle coated with graphene shells with nitrogen dopants (abbr. MoCx@C-1) is prepared from an entangled polyoxometalate-encapsulated coordination polymer (PECP), [Zn(bimbp)2]3[PMo12O40]2·2H2O (PECP-1) (bimbp = 4,4′-bis(imidazolyl)biphenyl) via the annealing and etching processes. The synergistic effects between highly dispersive MoCx particles, graphene coatings and N dopants in MoCx@C-1 lead to remarkable HER performance in acidic media with a very positive onset potential close to that of commercial 20% Pt/C catalysts, a low Tafel slope of 56 mV dec−1, a high exchange current density of 0.27 mA cm−2, and superior long-term cycle stability. In particular, MoCx@C-1 exhibiting an overpotential of 79 mV at a current density of 10 mA cm−2 represents one of the currently best reported MoCx-based HER electrocatalysts in acidic media. Such performance is also better than that of uncoated MoCx-2 nanoparticles prepared by carburizing another PECP [Bu4N][Zn3(bimb)4Cl(MoO4)][PMoVMoVI11O40]·4H2O (PECP-2) (bimb = 1,4-bis(1-imidazolyl)benzene). This work provides a new feasible route to prepare nanostructured hybrids composed of transition metal carbides, graphene and N dopants with higher HER activity and stability. [ABSTRACT FROM AUTHOR]

There is increasing evidence that microstructures play an important role in the maintenance of the multipotency of stem cells. However, it is not clear how micropatterns affect the stemness of stem cells. We prepared micropatterns of different sizes, shapes and aspect ratios and used them for the culture of mesenchymal stem cells (MSCs) derived from human bone marrow to investigate their influence on the stemness of MSCs at the single cell level. The percentage of cells positively stained by stem cell markers decreased with increasing spreading area and aspect ratio. However, the cellular geometry controlled by the geometrical micropatterns had no significant influence on the expression of stem cell markers. The change in the stemness of stem cells was accompanied by changes in the nuclear activity and cytoskeleton. The nuclear activity increased with increasing spreading area and aspect ratio. The actin filament structure was significantly influenced by the spreading area and aspect ratio. The cells became stiffer when they had sufficient area to spread into or when they were elongated. These results suggest that controlling the cell morphology by micropatterns may be useful in varying the stemness of MSCs. This study will contribute to the design of materials for maintaining the multipotency of stem cells, enhancing their clinical application and helping to reveal the processes taking place under conditions of stem cell quiescence in vivo. [ABSTRACT FROM AUTHOR]

Recently, modifying TiO2 to develop visible-light-driven photocatalysts via doping with nonmetal elements, metals and semiconductors has attracted much attention. In this study, a facile and reproducible sol–gel method was utilized for the first time to codope nonmetal (P), metal (Ag) and narrow band gap semiconductors (Ag2O and Ag3PO4) in TiO2 to prepare a P/Ag/Ag2O/Ag3PO4/TiO2 composite photocatalyst for developing a novel visible-light-driven photocatalyst. The crystal structure, morphology and optical properties of P/Ag/Ag2O/Ag3PO4/TiO2 were systemically characterized, and the photocatalytic abilities were evaluated under simulated solar light, in comparison with pure TiO2 and Ag/Ag2O/TiO2 photocatalysts. The results indicated that the P/Ag/Ag2O/Ag3PO4/TiO2 composite photocatalyst exhibited a strong absorption band in the visible light region, a small band gap (about 2.2 eV) and extremely high separation efficiency of photo-excited electron–hole pairs, which could account for its enhanced photocatalytic performance. The degradation ratio of rhodamine B (Rh B) by P/Ag/Ag2O/Ag3PO4/TiO2 reached 97.1% after 60 min under simulated solar light with only 13 mW cm−2 light intensity, while just 26.6% and 66.7% of Rh B were degraded by the as-prepared TiO2 and Ag/Ag2O/TiO2 photocatalysts, respectively. Furthermore, the radical trapping experiments implied that photo-generated holes and O2Ṗ− radicals in the P/Ag/Ag2O/Ag3PO4/TiO2 composite photocatalyst were the major active species for Rh B degradation. Metallic Ag could effectively trap the photo-generated electrons from Ag3PO4 and Ag2O to reduce the possibility of decomposing Ag3PO4 and Ag2O, resulting in an improved stability of the P/Ag/Ag2O/Ag3PO4/TiO2 composite with high photocatalytic ability. [ABSTRACT FROM AUTHOR]