Abstract: Metal nanoparticles have received intense scientific attention in the field of catalysis Precise engineering of nanomaterials’ size, shape and surface composition, including adsorbed capping ligands, is of utmost importance to control activity and selectivity, and distinguish colloidally prepared metal nanoparticle catalysts from traditional heterogeneous catalysts The interface between the material and the reaction medium is where the key interactions occur; therefore, catalysis occurs under the influence of capping ligands In this Perspective review, we focus on the choice of capping ligands (or stabilizing agents), and their role and fate in different steps from preparation to catalysis Evaluating the influence of the ligands on the catalytic response is not trivial, but the literature provides examples where the ligands adsorbed on the nanoparticle surface dramatically change the activity and selectivity for a particular reaction, while acting either as a dynamic shell or a passivation coating Steric and electronic effects resulting from the presence of adsorbed ligands have been proposed to influence the catalytic properties Attempts to remove the capping ligands are discussed, even though they are not always successful or even necessary Finally, we outline our personal understanding and perspectives on the use of ligands or functionalized supports to tune the activity and selectivity of supported metal nanoparticles

Abstract: The clinical success of the platinum-based chemotherapeutic agents has prompted the investigation of coordination and organometallic complexes of alternative metal centers for use as anticancer agents. Among these alternatives, the third row transition metal neighbors of platinum on the periodic table have only recently been explored for their potential to yield anticancer-active complexes. In this Perspective, we summarize developments within the last six years on the application of rhenium, osmium, and iridium complexes as anticancer drug candidates. This review focuses on studies that discuss the potential mechanisms of action of these complexes. As reflected in this Perspective, complexes of these metal ions induce cancer cell death via a diverse range of mechanisms. Notably, small structural changes can significantly alter the mode of cell death, hindering efforts to elucidate structure–activity relationships. This property may both benefit and hinder the clinical development of these compounds.

Abstract: Metal–organic frameworks (MOFs) have emerged as a new platform for the construction of various functional materials for energy related applications. Here, a facile MOF templating method is developed to fabricate a hierarchical nickel–cobalt sulfide nanosheet array on conductive Ni foam (Ni–Co–S/NF) as a binder-free electrode for supercapacitors. A uniform 2D Co-MOF nanowall array is first grown in situ on Ni foam in aqueous solution at room temperature, and then the Co-MOF nanowalls are converted into hierarchical Ni–Co–S nanoarchitectures via an etching and ion-exchange reaction with Ni(NO3)2, and a subsequent solvothermal sulfurization. Taking advantage of the compositional and structural merits of the hierarchical Ni–Co–S nanosheet array and conductive Ni foam, such as fast electron transportation, short ion diffusion path, abundant active sites and rich redox reactions, the obtained Ni–Co–S/NF electrode exhibits excellent electrochemical capacitive performance (1406.9 F g−1 at 0.5 A g−1, 53.9% retention at 10 A g−1 and 88.6% retention over 1000 cycles), which is superior to control CoS/NF. An asymmetric supercapacitor (ASC) assembled by using the as-fabricated Ni–Co–S/NF as the positive electrode and activated carbon (AC) as the negative electrode delivers a high energy density of 24.8 W h kg−1 at a high power density of 849.5 W kg−1. Even when the power density is as high as 8.5 kW kg−1, the ASC still exhibits a high energy density of 12.5 W h kg−1. This facile synthetic strategy can also be extended to fabricate other hierarchical integrated electrodes for high-efficiency electrochemical energy conversion and storage devices.

Abstract: Metal-organic frameworks (MOFs), also known as coordination polymers, have attracted extensive research interest in the past few decades due to their unique physical structures and potentially vast applications. In this review, we outline the recent progress in the synthesis, functionalization and applications of MOFs in biomedicine, mainly focusing on two promising, yet challenging areas, i.e., drug delivery and biosensing applications. A major challenge is the proper functionalization of MOFs with demanding properties suitable for biomedical applications. Extensive studies on MOFs in biomedicine have led to substantial progress in the control of key properties of MOFs such as toxicity, size and shape, and biological stability. Due to their flexible composition, pore size and easy functionalization properties, MOFs can be utilized as key components for the development of various functional systems, and their applications in drug delivery and biosensing are reviewed. Future trends and perspectives in these research areas are also outlined.

Abstract: Two 3D metal–organic frameworks (MOFs) with different structures, [Cu(4,4′-bipy)Cl]n (1) and [Co(4,4′-bipy)·(HCOO)2]n (2), were synthesized by means of a hydrothermal method using a typical ligand (4,4′-bipyridine), and characterized by elemental analyses, thermal analyses and single crystal X-ray diffraction As MOF materials, the two complexes showed active performance for the photodegradation of methylene blue (MB) dye under visible light MB degradation over the two MOF-based photocatalysts follows first-order kinetics The addition of an H2O2 electron acceptor can markedly enhance the photocatalytic MB degradation performance via a ligand-to-metal charge transfer mechanism, especially in complex 1 Complex 1 is better than complex 2 in MB photodegradation performance under the same conditions Moreover, complex 1 showed a stable activity for MB degradation after four consecutive usages Owing to the advantages of the visible light response, stable structure, low cost and high yield, these MOF-based photocatalysts will facilitate new efforts in environmental purification

Abstract: A zinc(II) coordination polymer {[Zn3(mtrb)3(btc)2]·3H2O}n (1) was synthesized and characterized (mtrb = 1,3-bis(1,2,4-triazole-4-ylmethyl)benzene, btc = 1,3,5-benzenetricarboxylate). The polymer 1 shows an unusual (3,4,4)-coordinated self-catenated 3D network with the point symbol of {63}2{62·82·102}{64·82}2. The polymer 1 is the first luminescent sensor for the detection of 2-amino-4-nitrophenol (ANP). The polymer 1 is also a good luminescence sensor for detection of TNP, 2,4-DNP, 4-NP, ANP and 2-NP in MeOH, particularly for TNP. The order of detection efficiency is TNP > 2,4-DNP > 4-NP > ANP > 2-NP. The polymer 1 also exhibits high sensitivity and selectivity as a luminescence sensor for the detection of Fe3+, Cr2O72− and CrO42− in aqueous solution. Our experiments showed that the presence of interfering ions had no significant effect on the sensing of Fe3+, Cr2O72− or CrO42− ions. The detection limits for TNP, ANP, Fe3+, Cr2O72− and CrO42− are 0.22 μM, 4.12 μM, 1.78 μM, 2.83 μM, and 4.52 μM, respectively. The luminescence sensor is stable and can be recycled for detection at least five times. The possible quenching mechanisms are discussed. The polymer 1 is also an effective photocatalyst for degradation of methylene blue (MB) under visible or UV light irradiation.

Abstract: This review provides a brief background on the extraction of uranium from seawater as well as recent work by the United States Department of Energy on this project. The world's oceans contain uranium at 3 parts per billion, and despite this low concentration, there has been historical interest in harvesting it, mainly in Japan in the 1980s and the United States in this decade. Improvements in materials, chemistry, and deployment methods have all been made, with the ultimate goal of lower cost. This has been partially realized, dropping from approximately $2000 per kg U3O8 extracted in 1984 to $500 per kg today, although this is not yet competitive with terrestrial uranium. This technology may become cost-competitive if the cost of land-based uranium rises, especially if seawater extraction technology is improved further. The coordination chemistry aspects of the project are described in more detail, exploring the functional groups that are present on typical polymer sorbents as well as small-molecule analogues of these ligands. Selectivity for uranium over other metals, particularly vanadium, remains problematic, and techniques to both quantify binding strength and selectivity in order to overcome this issue are essential for future cost improvements.

Abstract: Metal-organic frameworks (MOFs) show great advantages as new kinds of active materials for energy storage. In this study, bimetallic metal-organic frameworks (Ni/Co-MOFs) with nanosheet-assembled flower-like structures were synthesized by etching Ni-MOF microspheres in a cobalt nitrate solution. It can be clearly observed that the amount of Co(NO3)2 and etching time play crucial roles in the formation of Ni/Co-MOF nanosheets. The Ni/Co-MOFs were used as electrode materials for supercapacitors and the optimized Ni/Co-MOF-5 exhibited the highest capacitances of 1220.2 F g-1 and 986.7 F g-1 at current densities of 1 A g-1 and 10 A g-1, respectively. Ni/Co-MOF-5 was further sulfurized, and the derived Ni-Co-S electrode showed a higher specific capacitance of 1377.5 F g-1 at a current density of 1 A g-1 and a retention of 89.4% when the current density was increased to 10 A g-1, indicating superior rate capability. Furthermore, Ni/Co-MOF-5 and Ni-Co-S showed excellent cycling stability, i.e. about 87.8% and 93.7% of initial capacitance can be still maintained after 3000 cycles of charge-discharge. More interestingly, the Ni/Co-MOF-5//AC ASC shows an energy density of 30.9 W h kg-1 at a power density of 1132.8 W kg-1, and the Ni-Co-S//AC ASC displays a high energy density of 36.9 W h kg-1 at a power density of 1066.42 W kg-1. These results demonstrate that the as-synthesized bimetallic Ni/Co-MOF nanosheets and their derived nickel-cobalt sulfides have promising applications in electrochemical supercapacitors.

Abstract: Ternary NiCoFe mixed-metal oxides (NCF-MMOs) with different Ni/Co/Fe ratios were successfully synthesized through a hydrotalcite-like precursor route by co-precipitation of appropriate amounts of metal salts from homogeneous solution, followed by calcination at 600 °C. X-ray diffraction (XRD) patterns revealed the formation of well crystalline layered double hydroxides (LDHs), particularly at the M2+/M3+ ratio of 3 : 1. Brunauer-Emmett-Teller (BET) analysis revealed that the resulting NiCoFe LDHs possessed large specific surface areas (66.9-93.8 m2 g-1). The NCF-MMO (1 : 2 : 1) samples were demonstrated to be formed by the aggregation of regular cubes with an edge length of about 2 μm, and each cube was accumulated with many fine particles with a size of ∼130 nm. UV-vis diffuse reflection spectroscopy (DRS) confirmed that the samples showed a broad absorption in the visible-light region (450-750 nm), with a low band gap of 2.33-2.77 eV. The calcined samples with a Ni/Co/Fe molar ratio of 1 : 2 : 1 possessed the best photocatalytic activity with 96.8% degradation of methylene blue (MB) dye under visible light irradiation for 4 h, which exceeded those of commercial P25 TiO2, binary NiFe mixed-metal oxides and pure Fe2O3, CoO and NiO particles under the same conditions. NCF-MMO (1 : 2 : 1) also had a strong degradation effect on the non-dye pollutant phenol as well. Kinetic studies suggested that the degradation of MB followed a pseudo-first-order kinetic behavior. The photodegradation mechanism of NCF-MMOs was also discussed.

Abstract: The global electrophilicity index, GEI, is used as a general, quantitative and base-independent metric of Lewis acidity. This parameter has been benchmarked against the established fluoride ion affinity, FIA, for a range of 22 neutral and cationic Lewis acids from across the p-block, including boranes, trityl derivatives, phosphonium cations and sulfoxonium cations. As a demonstration of utility, the GEI is used to catalogue a library of fluoroaryl boranes as it provides a rapid tool for the comparison of a series of Lewis acids featuring peripheral substituent variation.

Abstract: Three isostructural metal–organic frameworks denoted as Zn(L)(aip)·(H2O) (1), Zn(L)(ip)·(DMF)(H2O)1.5 (2), and Zn(L)(HBTC)·(H2O)2 (3) with functional groups –NH2, –H and –COOH, respectively, decorated on the 1D channels have been rationally designed with the purpose of exploring the influence of electron transfer from organic ligands in the 1D channels on the sensing of nitro explosives and antibiotics. These three compounds exhibit strong fluorescence in water, and they can be applied to detect the presence of explosives or antibiotics by means of fluorescence quenching in aqueous solution, whereas in terms of special explosives or antibiotics at the same concentration, 3 demonstrates a more superior quenching efficiency than 1 and 2. More importantly, it has been found that the difference in the sensing performances of these compounds is closely related to the interaction between the functional groups and guest molecules via electron and energy transfer from MOFs to explosives and antibiotics.

Abstract: A novel multi-component and binder-free electrode material of NiCo2O4 (NCO) nanoplates adhered to NiMoO4 (NMO) honeycomb composites was prepared on a nickel foam (NF) using a simple chemical bath deposition strategy. This paper reports the synthesis of a honeycomb composite with folded silk-like NF@NMO@NCO nanostructures on nickel foam and its use to increase the availability of electrochemically active sites to provide additional pathways for electron transport and improve the utilization rate of the electrode materials. As a result, the as-fabricated NF@NMO@NCO electrode exhibited a maximum specific capacitance of 2695 F g−1 at a current density of 20 mA g−2, which is much better than that of NF@NCO nanoplates (1018 F g−1) and NF@NMO honeycomb (1194 F g−1). Moreover, the as-synthesized NF@NMO@NCO achieved a high energy density of 61.2 W h kg−1 and outstanding power density of 371.5 W kg−1 as well as exceptional capacitance retention of 98.9% after 3000 cycles. The outstanding electrochemical performance makes the honeycomb composite with a folded silk-like nanostructure a promising candidate for advanced electrochemical energy storage.

Abstract: Iron-containing metal-organic frameworks (MOFs) have gradually emerged as environmentally benign alternatives for reducing the levels of environmental contamination because of their advantages, such as readily obtained raw materials with low cost, nontoxic metal source with good biocompatibility, and distinguished physicochemical features e.g., high porosity, framework flexibility, and semiconductor properties. In this study, we reported an innovative strategy for synthesizing an iron-based MOF, MIL-88B, at room temperature. The novelty of this strategy was the use of ethanol as solvent and the pretreatment of dry milling with neither the bulk use of a toxic organic solvent nor the addition of extremely dangerous hydrofluoric acid or strong alkali. The synthesized MIL-88B(Fe) was evaluated as a sorbent for removing arsenate in water and it exhibited high adsorption capacity (156.7 mg g-1) at a low dosage. The removal capacity of trace arsenate on MIL-88B(Fe) was 32.3 mg g-1 at a low equilibrium concentration (6.4 μg L-1), which satisfied the arsenic threshold for drinking water. The results of Fourier transform infrared and X-ray photoelectron spectroscopy indicated that the As(v) molecules bonded with the oxygen molecules, which were coordinated with FeO clusters in the framework. This work presented the potential use of the up-scaled MIL-88B as an excellent sorbent for purifying arsenate-contaminated water.

Abstract: Fast and highly selective detection of trace amounts of metal ions has become one of the most urgent issues concerning public security and living systems However, developing a highly efficient fluorescent sensor for metal ions still remains a great challenge Metal–organic frameworks (MOFs) are a promising class of porous fluorescent sensors towards ion detection Herein, the anionic MOF FJI-C8 based on the π-conjugated aromatic ligand H6TDPAT (2,4,6-tris(3,5-dicarboxylphenylamino)-1,3,5-triazine) containing uncoordinated nitrogen and carboxylate oxygen atoms was chosen as highly efficient sensor for selective detection of Fe3+ Due to the strong interaction between Fe3+ and Lewis base sites (uncoordinated nitrogen and carboxylate oxygen atoms), the high overlap between the emission spectrum of the anionic FJI-C8 and the absorption spectrum of Fe3+, and the good overlap of the excitation spectrum of the host material FJI-C8 with the absorption spectrum of Fe3+, FJI-C8 exhibited a high sensitivity (00233 mM of Fe3+) and extra selectivity (Ksv = 8245 M−1) for the rapid detection (less than 30 s) of Fe3+ with low usage (004 mg mL−1 of FJI-C8 suspension) To the best of our knowledge, this is the first example of a luminescent MOF chemosensor based on a trefoil ligand with the highest density of uncoordinated N and carboxylate O atoms for the highly selective detection of Fe3+ It is also crucial to note that this is a first time detection of Fe3+ using both FJI-C8 suspension and solid after filtration, and the results indicate that the detection of Fe3+ using the FJI-C8 suspension is better This study will pave the way for designing luminescent MOF chemosensors for the detection of Fe3+ ion

Abstract: With admirable luminescence performance and a cheap price, non-rare-earth-based oxide red phosphors are a potential competitor of rare-earth-doped phosphors for warm white LEDs (WLEDs). Herein, a novel double-perovskite Ba2GdSbO6:Mn4+ phosphor, demonstrating strong red emission ascribed to a spin-forbidden Mn4+:2Eg → 4A2g transition in the region of 620-750 nm, has been synthesized via a solid-state reaction route. The microstructure and luminescence properties are investigated in detail. The concentration quenching mechanism and thermal stability based on thermal quenching characteristics are also discussed. Importantly, Li+, Mg2+, Zn2+, Si4+, Ti4+ and Ge4+ dopants are discovered to be beneficial for enhancing Mn4+ luminescence, and the related mechanisms are comprehensively described. In addition, by combining red-emitting Ba2GdSb0.994O6:0.003Mn4+,0.003Mg2+ with the commercial blue-emitting BaMgAl10O17:Eu2+ and green-emitting Ba3La6(SiO4)6:Eu2+ phosphors in various ratios, a series of WLED devices with a tunable correlated color temperature (CCT) evolving from 6256 to 3486 K and a color rendering index (CRI) increasing from 72.1 to 88.3 are achieved.

Abstract: In this article, we report the preparation and luminescence properties of a series of novel rare-earth doped KBaY(MoO4)3 phosphors. The XRD patterns for the as-prepared samples have been assigned to the pure KBaY(MoO4)3 phase. The Tb3+, Eu3+ and Sm3+ singly-doped phosphors all show good luminescence properties with their characteristic excitations and emissions. We have optimized the rare-earth ion doping concentrations, yielding the compositions KBaY0.60(MoO4):0.40Tb3+, KBaY0.50(MoO4):0.50Eu3+ and KBaY0.96(MoO4):0.04Sm3+ with corresponding quantum yields of 15.80% (λex = 376 nm), 40.67% (λex = 392 nm) and 16.79% (λex = 402 nm), respectively. In addition, we have chosen co-doping of Tb3+/Eu3+ and Tb3+/Sm3+ into the host to realize tunable emission colors. We have observed energy transfer from Tb3+ to Eu3+ and from Tb3+ to Sm3+ ions in the as-prepared samples, which resulted in tunable emission colors from green to red and to orange-red under UV excitation, respectively. Moreover, investigation of the excitation and emission spectra, and decay lifetimes with increasing doping concentrations confirmed efficient energy transfer from Tb3+ to Eu3+ and from Tb3+ to Sm3+ ions in the co-doped samples. We also analyzed the energy transfer mechanisms between Tb3+ and Eu3+ and between Tb3+ and Sm3+ and both were determined to be dipole-dipole interactions. These results show that the as-prepared materials could serve as candidate phosphors for use in UV-pumped w-LEDs.

Abstract: Photodynamic therapy (PDT) involves the combination of non-toxic dyes called photosensitizers (PS) and harmless visible light that interact with ambient oxygen to give reactive oxygen species (ROS) that can damage biomolecules and kill cells. PDT has mostly been developed as a cancer therapy but can also be used as an antimicrobial approach against localized infections. However even the longest wavelength used for exciting PS (in the 700 nm region) has relatively poor tissue penetration, and many PS are much better excited by blue and green light. Therefore upconversion nanoparticles (UCNPs) have been investigated in order to allow deeper-penetrating near-infrared light (980 nm or 810 nm) to be used for PDT. NaYF4 nanoparticles doped with Yb3+ and Er3+ or with Tm3+ and Er3+ have been attached to PS either by covalent conjugation, or by absorption to the coating or shell (used to render the UCNPs biocompatible). Forster resonance energy transfer to the PS then allows NIR light energy to be transduced into ROS leading to cell killing and tumor regression. Some studies have experimentally demonstrated the deep tissue advantage of UCNP-PDT. Recent advances have included dye-sensitized UCNPs and UCNPs coupled to PS, and other potentially synergistic drug molecules or techniques. A variety of bioimaging modalities have also been combined with upconversion PDT. Further studies are necessary to optimize the drug-delivery abilities of the UCNPs, improve the quantum yields, allow intravenous injection and tumor targeting, and ensure lack of toxicity at the required doses before potential clinical applications.

Abstract: Due to the high emissions of CO2 and the related environmental impact, the chemical transformation of CO2 to useful industrially relevant products or their precursor is of significant interest. Recycling CO2 as a building block for the synthesis of chemicals may not only reduce further emission by at least replacing oil-derived feedstocks, but also provide the advantages of CO2 as an inexpensive, non-toxic and easily available substrate. The catalytic conversion of CO2 into small, useful molecules such as carbonates, methyl amines, methanol, formic acid, etc. by molecular catalysts is an interesting topic that has strongly developed in recent years. This review provides an overview of current scientific progress in the activation and conversion of carbon dioxide with industrially and scientifically relevant substrates using molecular catalysts. Metal-based catalysts are presented in the first part of the review whereas metal-free systems are described in the second part.

Abstract: It is known that heterojunction photoelectrodes can improve light absorption and accelerate the separation of photogenerated carriers in the field of photoelectrochemical (PEC) water splitting. However, the key to efficient photoelectrochemical performance is to build heterojunctions with a narrow band gap semiconductor loaded on a wide band gap semiconductor uniformly and densely. Herein, a ZnO/ZnFe2O4 uniform core–shell heterojunction photoelectrode is prepared by a simple ion etching method. Moreover, the chemical reaction process and mechanism are discussed in detail. The ZnO/ZnFe2O4 photoelectrode shows a higher photocurrent density (0.29 mA cm−2 at 1.23 V vs. RHE) compared with that of ZnO (0.17 mA cm−2 at 1.23 V vs. RHE). Furthermore, the PEC performance of ZnO/ZnFe2O4 is optimized by depositing NiOOH; the photocurrent density of ZnO/ZnFe2O4/NiOOH is 0.48 mA cm−2 at 1.23 V vs. RHE. The remarkable PEC performance of ZnO/ZnFe2O4/NiOOH benefits from the following important factors: (i) the uniformity and nanotube structure of the ZnO/ZnFe2O4 heterojunction; (ii) the excellent light harvesting ability; and (iii) the reduced photogenerated electron–hole pair recombination rate. This work provides new insights into designing heterojunction systems for efficient photoelectrochemical water splitting.

Abstract: A modified MOF named UiO-66-NH2-SA was synthesized based on the covalent post synthetic attachment of the MOFs (UiO-66-NH2) and salicylaldehyde via a Schiff-base reaction. The as-prepared functionalized UiO-66-NH2-SA not only maintains its structural integrity during the PSM process, but also shows excellent luminescence and good fluorescence stability in water. It was further utilized as a novel fluorescent probe for detecting of Al3+. The fluorescence intensity of UiO-66-NH2-SA increased linearly upon increasing the concentration of Al3+ in the range of 0–500 μM with a detection limit of 6.98 μM. The possible mechanism is discussed. This study presents a new ratiometric and colorimetric Al3+ fluorescent sensor. The good fluorescence stability of UiO-66-NH2-SA in aqueous media, the low detection limit and the broad linear in sensing Al3+ indicate its high potential in practical applications.

Abstract: The development of metal–organic framework sensors with excellent stability under harsh physical and chemical conditions is of great significance in practical applications. Two isostructural lanthanide–organic frameworks, Ln-MOF ({Ln(L)(H2O)(DMA)}n, {FJU-13-Ln, Ln = Eu, Tb } (H3L = 3,5-(4-carboxybenzyloxy)benzoic acid)), were found to display exceptional stability, not only being stable in both acidic and basic aqueous solutions (pH 3–11), but also maintaining good robustness in boiling water and after activation. Furthermore, the plentiful oxygen atoms in the oxygen-rich channels of FJU-13-Eu and FJU-13-Tb acted as Lewis base sites for sensing metal ions, exhibiting high sensitivity (Stern–Volmer constant, KSV = 2.03 × 104 M−1 for FJU-13a-Eu and KSV = 2.11 × 104 M−1 for FJU-13a-Tb) and low detection limits (1.41 μM for FJU-13a-Eu and 1.01 μM for FJU-13a-Tb) for Fe3+ ions. This suggests that the two Ln-MOFs are promising fluorescent sensors for Fe3+ ion detection.

Abstract: Searching for highly active and stable bifunctional electrocatalysts for overall water splitting, e.g., for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), is dominating in terms of bringing future renewable energy storage and conversion processes to reality. In this work, a kind of two-dimensional ultrathin manganese (Mn) doped polyhedral cobalt phosphide (Mn-CoP) has been synthesized via the etching-carbonization-phosphidation of Co-centered metal-organic frameworks. The as-prepared porous Mn-CoP nanosheets had a larger specific surface area and higher porosity, furnishing them with more plentiful catalytically active sites than their counterpart hollow CoP and Mn-CoP nanoparticles, and thus showed much better electrocatalytic activity for both HER and OER in acidic and alkaline media. In addition, the Mn-CoP nanosheets also demonstrated excellent durability after long-term operation. These high performances are attributed to the synergistic effects of the CoP nanosheets with intrinsic activity, the graphitic carbon and the controllable electronic structure doped by Mn and N elements. This synthetic methodology of using a classical MOF as a precursor to build a new 2D sheet-like composite may create opportunities to search for highly efficient and robust non-precious metal catalysts for energy-related reactions.

Abstract: Owing to its low-cost and satisfactory luminescent-emission performance in warm white light-emitting diodes (w-LEDs), the non-rare-earth Mn4+-activated red phosphor has become a promising competitor of commercial rare-earth doped phosphor. In this study, a series of novel red-light emitting phosphors based on Ca2YSbO6:Mn4+ have been developed successfully by a conventional solid-state reaction. The structural and luminescent properties of these phosphors are systematically investigated. The as-prepared Ca2YSbO6:Mn4+ product exhibits a broad excitation band ranging from 250 to 600 nm and an abnormal intense deep-red emission centered at 680 nm with a full width at half maximum (FWHM) of ∼46 nm. The optimal Mn4+ doping concentration is about 0.3 mol%, and the concentration quenching mechanism is determined to be a dipole–dipole interaction. Impressively, the Ca2YSbO6:0.003Mn4+ phosphor shows an outstanding quantum efficiency of 62.6% and an excellent thermal stability. In addition, the effect of Li+, Mg2+, Na+ and K+ dopants on the luminescent properties of Mn4+-doped Ca2YSbO6 phosphors is elucidated. Furthermore, by employing the as-prepared Ca2YSbO6:Mn4+ as a red component, a warm w-LED with high color rendering index (Ra = 87.5) and low correlated color temperature (CCT = 3255 K) can be acquired. It is believed that the present phosphor has a potential application as a supplement of the red component for warm w-LEDs.

Abstract: We have synthesized a core@shell nanocomposite using biocompatible bovine serum albumin (BSA) as the core and a pH-sensitive metal-organic framework (MOF) as the shell. Doxorubicin (DOX)/BSA nanoparticles as cores have been prepared. A zeolitic imidazolate framework-8 (ZIF-8) layer has been coated on the outer surface of the DOX/BSA core. The ZIF layer acts as a capsule for the safe storage of DOX under physiological conditions. An efficient pH-responsive drug delivery system using a BSA/DOX@ZIF, in which the drug is not released in PBS at pH 7.4 but is released at low pH (5.0-6.0), has been constructed. Compared to the pure ZIF, a better biocompatibility has been obtained using the BSA/DOX@ZIF. The BSA/DOX@ZIF shows a much higher efficacy than free DOX against the breast cancer cell line MCF-7. The positive charges on the outer surface of the BSA/DOX@ZIF also improve its cellular uptake.

Abstract: In this work, a novel deep red-emitting phosphor KMgLaTeO6:Mn4+ potentially used in w-LEDs is reported, which can be efficiently excited with UV or blue light with a high quantum yield of 68.9% upon 365 nm excitation. More importantly, the luminescence thermal stability of this kind of phosphor shows excellent performance.

Abstract: Two multifunctional, ether-bridged tricarboxylic acids, 2-(4-carboxylphenoxy)terephthalic acid (H3cpta) and 2-(3,5-dicarboxylatobenzyloxy)benzoic acid (H3dbba), were used as unexplored and highly versatile building blocks for the hydrothermal generation of a novel series of cadmium(ii) metal-organic architectures. These were formulated as [Cd(μ-Hcpta)(phen)(py)]n (1), {[Cd3(μ5-cpta)2(phen)3]·8H2O}n (2), {[Cd3(μ5-cpta)2(2,2'-bipy)3]·6H2O}n (3), {[Cd(μ3-cpta)(Hbpa)]·2H2O}n (4), {[Cd6(μ4-cpta)2(μ6-cpta)2(H2biim)2(H2O)6]·5H2O}n (5), [Cd3(μ4-cpta)2(μ-prz)(H2O)4]n (6), {[Cd3(μ4-dbba)2(phen)3]·H2O}n (7), and {[Cd3(μ3-dbba)2(2,2'-bipy)3(H2O)3]·2H2O}n (8) on the basis of single-crystal X-ray diffraction, elemental analysis, FTIR, PXRD, and TGA data. Products 1-8 were assembled in the presence of N-donor crystallization mediators selected from pyridine (py), 1,10-phenanthroline (phen), 2,2'-bipyridine (2,2'-bipy), bis(4-pyridyl)amine (bpa), 2,2'-biimidazole (H2biim), or piperazine (prz). The nature of the crystallization mediator and/or the type of principal tricarboxylate building block have a significant effect on the structural diversity, dimensionality, and topology of the resulting cadmium-organic architectures. These span from 1D (1, 8) and 2D (7) coordination polymers to 3D metal-organic frameworks (2-6) with intricate topologies (3,4,5T64 in 2 and 3, utp (103)-d in 4, 3,4,4T9 in 6) that also include unprecedented types in 5 and 7. Besides, MOF 6 features a 3D + 3D two-fold interpenetrated framework. Luminescent and photocatalytic properties of selected materials were investigated, showing that coordination polymer 7 is a promising photocatalyst for the UV-light-driven degradation of methylene blue as a model organic dye pollutant. Moreover, products 7 and 8 are the first examples of structurally characterized coordination compounds derived from H3dbba.

Abstract: The articulate combination of intriguing functional groups and luminescence properties can deliver metal-organic frameworks (MOFs) with multifarious applications viz. selective and specific sensing of nitroaromatic compounds (NACs), an important constituent of explosives, as well as sensing of toxic metal ions. In this regard, a new d10 configuration based Zn(ii) metal-organic framework (MOF) {(NH2(CH3)2)[Zn4(ddn)2(COO)(H2O)4]·solvent}n (1) has been synthesized using a π-conjugated and rigid multicarboxylate ligand 3,5-di(3,5-dicarboxylphenyl)nitrobenzene (H4ddn). 1 displays a 3D (3,4,6)-c connected net which is based on two types of binuclear [Zn2(μ2-COO)2(μ1-COO)2] and [Zn2(μ2-COO)4] clusters. Sensing studies of 1 to detect nitro-aromatic compounds reveal highly specific detection of 2,4-dinitophenol (DNP) with remarkable quenching (KSV = 8.93 × 103 M-1) and a low limit of detection (LOD: 1.12 ppm). The luminescence quenching mechanism in the case of 1 in the presence of NACs has been ascribed to the concurrent presence of the charge transfer as well as the weak interaction between the MOF and NACs. The activated framework of 1 also displayed highly selective detection of ferric ions with KSV = 1.13 × 104 M-1 with a low limit of detection (LOD: 1.24 ppm).

Abstract: Enabling the optimal usage of solar energy is considered to be one of the most pressing challenges in the photocatalytic remediation of water resident contaminants. Herein, a single-atom dispersed Ag loaded ultrathin g-C3N4 hybrid (AgTCM/UCN) was prepared through a facile co-polymerization of dicyandiamide with silver tricyanomethanide (AgTCM) and NH4Cl, and used as a visible light driven photocatalyst for the degradation of sulfamethazine (SMT) in the presence of peroxymonosulfate (PMS). Under UV light, visible light and simulated sunlight irradiation, the AgTCM/UCN/PMS process showed higher efficiency for SMT degradation than AgTCM/UCN, UCN/PMS, and g-C3N4/PMS systems. This enhanced photocatalytic activity may be attributed to the synergistic effects encompassing the surface plasmon resonance (SPR) of Ag, high surface area of UCN, and efficient charge separation of PMS. Electron-spin resonance (ESR) and reactive species (RSs) scavenger-quenching experiments revealed that SO4˙- was generated following the addition of PMS, whereas O2˙- and h+ were predominantly responsible for the degradation of SMT. Three degradation pathways of SMT were deduced, including the cleavage of sulfonamide bonds, SO2 extrusion, and the oxidation of the aniline moiety, based on mass spectrometry and theoretical calculations. The degradation of SMT in ambient water revealed that the AgTCM/UCN/PMS photocatalytic process can be efficaciously applied for the remediation of SMT contaminated natural waters, particularly sea water.

Abstract: A Cu2O/BiVO4 p-n heterojunction based photoanode in photoelectrochemical (PEC) water splitting is fabricated by a two-step electrodeposition method on an FTO substrate followed by annealing treatment. The structures and properties of the samples are characterized by XRD, FESEM, HRTEM, XPS and UV-visible spectra. The photoelectrochemical activity of the photoanode in water oxidation has been investigated and measured in a three electrode quartz cell system; the obtained maximum photocurrent density of 1.72 mA cm-2 at 1.23 V vs. RHE is 4.5 times higher than that of pristine BiVO4 thin films (∼0.38 mA cm-2). The heterojunction based photoanode also exhibits a tremendous cathodic shift of the onset potential (∼420 mV) and enhancement in the IPCE value by more than 4-fold. The enhanced photoelectrochemical properties of the Cu2O/BiVO4 photoelectrode are attributed to the efficient separation of the photoexcited electron-hole pairs caused by the inner electronic field (IEF) of the p-n heterojunction.