Search

ITIC-series nonfullerene organic photovoltaics (NF OPVs) have realized the simultaneous increases of the short-circuit current density (JSC) and open-circuit voltage (VOC), called the positive correlation between JSC and VOC, which could improve the power conversion efficiency (PCE). However, it is complicated to predict the formation of positive correlation in devices through simple calculations of single molecules due to their dimensional differences. Here, a series of symmetrical NF acceptors blended with the PBDB-T donor were chosen to establish an association framework between the molecular modification strategy and positive correlation. It can be found that the positive correlation is modification site-dependent following the energy variation at the different levels. Furthermore, to illustrate a positive correlation, the energy gap differences (ΔEg) and the energy level differences of the lowest unoccupied molecular orbitals (ΔELUMO) between the two changed acceptors were proposed as two molecular descriptors. Combined with the machine learning model, the accuracy of the proposed descriptor is more than 70% for predicting the correlation, which verifies the reliability of the prediction model. This work establishes the relative relationship between two molecular descriptors with different molecular modification sites and realizes the prediction of the trend of efficiency. Therefore, future research should focus on the simultaneous enhancement of photovoltaic parameters for high-performance NF OPVs. [ABSTRACT FROM AUTHOR]

The anhydrous proton conductivity of Im@IEF-11 resulting from the integration of imidazole and porous IEF-11 has been investigated, and the highest proton conductive value can reach up to 7.64 × 10−2 S cm−1. Furthermore, IEF-11 is also developed to reduce CO2 due to its reasonable structure and suitable energy band, and its CO formation rate is 31.86 μmol g−1 h−1. [ABSTRACT FROM AUTHOR]

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

The room-temperature phosphorescence of 1,8-naphthalimide was activated by doping it into aromatic dicarboxylic acids. The doping system gives a bright yellow afterglow and 1,8-naphthalimide and isophthalic acid (0.02 mol% doping content) afford a phosphorescent lifetime of 403 ms and a quantum yield of 4.2%. Both energy transfer from the host to the guest and the formation of an intermolecular hydrogen-bonding network are responsible for the observed efficient and long-lived phosphorescence. [ABSTRACT FROM AUTHOR]

An unprecedented Mo–organic molecular cage built on interesting {Mo VI2 O5} secondary building blocks and BTC ligands, which has been successfully synthesized and systematically characterized, presents the first example of an isopolyoxomolybdates(VI)–organic molecular cage. An investigation into the related Cs+-exchange experiment was performed in detail. [ABSTRACT FROM AUTHOR]

We prepare a novel COF for CO2 photoreduction with 99.9% CO selectivity in aqueous solution without a cocatalyst. DFT shows that the preferential adsorption of H+ on the COF results in increased CO2 adsorption energy providing an anchoring site of CO2, and with the cooperation of an ethylene group, CO2 reduction is triggered. [ABSTRACT FROM AUTHOR]

A nanosized Ta/W mixed addendum polyoxometalate (Cs12K3H7[MnTa18Si6W54O231]·61H2O) based on the unprecedented {MnTa18} cluster was fabricated successfully under hydrothermal conditions. An excellent electrochemical performance of this compound was found in lithium-ion batteries (LIBs) as an anode material. The discharge capacity was 829.9 mA h g−1 at a current density of 100 mA g−1 in the first cycle and stable at 428.4 mA h g−1 after 100 cycles, which suggests the potential application of this new compound in LIBs. [ABSTRACT FROM AUTHOR]

A newly prepared tetraphenylethylene-based (TPE-based) covalent organic polymer (COP) named COP-1 exhibits high selectivity for sensing Fe3+ and the limit of detection (LOD) for Fe3+ is 0.42 μM, which is lower than the reported metal-free porous polymers. Furthermore, a WLED is fabricated and the CIE coordinates are (0.32, 0.33), very close to pure white light. The COP-1 shows potential applications in biosensors of Fe3+ and preparation of WLEDs. [ABSTRACT FROM AUTHOR]

Different from the previous design strategy, herein, a cationic Ir(iii) complex ([(ptbi)2Ir(bisq)]Cl) with a small chlorine as the counterion was synthesized, which realized the formation of a solid film via a vacuum-deposition process. The white OLED, employing it as an orange-emitting layer, achieved excellent performances with a brightness of 50 122 cd m−2, a CE of 25.5 cd A−1, an EQE of 13.1%, accompanied by a low CE efficiency roll-off of 4.7%. These are the best results among evaporated cationic Ir(iii)-based white OLEDs reported so far. [ABSTRACT FROM AUTHOR]

Dual catalysis has become a desirable alternative because of the synergetic effect of two distinct catalysts, but little is known about the mechanism of dual catalysis and its effect on the high reactivity and selectivity. Here, a novel Ullmann C–C cross-coupling of bromobenzene and 4-methoxyphenyltriflate via nickel/palladium dual catalysis has been investigated using density functional theory. The orthogonal reactivity of NiI/Pd0 combination is the precondition and foundation of achieving such a Ullmann cross-coupling reaction. In the present dual catalysis, the NiI complex acts as the primary catalyst, while the Pd0 catalyst plays a decisive role in the cross-selectivity. [ABSTRACT FROM AUTHOR]

A novel oxidation state modulation mechanism, merging oxidative quenching (IrIII–*IrIII–IrIV–IrIII) and nickel catalytic (NiII–NiI–NiIII–NiI–NiII) cycles, has been illuminated unambiguously for photoredox-mediated iridium(iii)/nickel(ii) dual catalyzed C–O cross-coupling of aryl bromide and alcohol. Quinuclidine participates in a crucial proton-coupled electron transfer process to accelerate the reaction and regulate C–O coupling selectivity. [ABSTRACT FROM AUTHOR]

The first CB[6]-based 3D porous metal–organic rotaxane framework is constructed by the reaction of CuCl2, terephthalic (H2BDC) and CB[6]-based [2]pseudorotaxanes ([PR44]2+·2[PF6]−) under solvothermal conditions. The structure of MORF-1 is a pillared-layer structure with 5-connected sqp topology, in which the effective free volume is 45.4% of the crystal volume. The guest molecules exchange in a single-crystal-to-single-crystal fashion, which was investigated using NMR spectroscopy and X-ray crystallography. [ABSTRACT FROM AUTHOR]

A novel polyoxometalate-based metal–organic framework (POMOF) with an ABW network, NENU-601, was synthesized in situ. To the best of our knowledge, this is the first POMOF with a zeolite-like structure, which was designed by regulating the length and angle of mixed ligands and rationally choosing suitable Polyoxometalates (POMs) as nodes. [ABSTRACT FROM AUTHOR]

Two novel isostructural polyoxometalate (POM)-based metal–organic frameworks (MOFs) with diamond topology, NENU-506 and NENU-507, were hydrothermally synthesized. They not only combine the advantages of both POMs and MOFs, but also show excellent chemical and thermal stability. Notably, NENU-507 exhibited a high reversible capacity of 640 mA h g−1 after 100 cycles when applied as an anode material in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

We have demonstrated for the first time that isostructural homochiral metal–organic frameworks (MOFs) can be synthesized directly from chiral ligands and indirectly from achiral ligands via spontaneous resolution combined with cooperative chirality induction, respectively. Moreover, the usage of different ligands leads to distinct proton conduction behaviors. [ABSTRACT FROM AUTHOR]

Two unprecedented polytantalotungstates (POTTs), Cs16K16Na4[Ta18P12W90(OH)6(H2O)2O360]·24H2O (1) and Cs26K2H2[Yb2Ta18P12W90(OH)6(H2O)16O360]·52H2O (2) based on the largest {Ta18} and {Ta18Yb2} clusters, respectively, were hydrothermally synthesized. A photocatalytic study revealed that 1 and 2 exhibit significant ultraviolet photocatalytic water splitting activity. [ABSTRACT FROM AUTHOR]

Unprecedented Anderson-like alkoxo-polyoxovanadate [V6O6(OCH3)9(μ6-SO4)(COO)3]2− polyanions can serve as 3-connected second building units (SBUs) that assemble with dicarboxylate or tricarboxylate ligands to form a new family of metal organic tetrahedrons of V4E6 and V4F4 type (V = vertex, E = edge, and F = face). To our knowledge, this alkoxo-polyoxovanadate-based SBU is the first ever reported. [ABSTRACT FROM AUTHOR]

A carbon-free, stable, homogeneous water oxidation catalyst based on the unique hepta-nuclear cobalt–arsenic core (“fused” double-quasi-cubane) and polyoxometalate ligands, Na12[{CoII7AsIII6O9(OH)6}(A-α-SiW9O34)2]·8H2O (1), was synthesized, thoroughly characterized and employed to catalyze water oxidation under visible-light-driven conditions. [ABSTRACT FROM AUTHOR]

A stable mesoporous blue-emitting MOF NENU-521 was successfully constructed. NENU-521 can serve as a host for encapsulating Alq3 to obtain tunable and efficient white-light emission. The Alq3@NENU-521 composite possesses excellent stability and can be used as a promising white phosphor in WLEDs. [ABSTRACT FROM AUTHOR]

An anionic metal–organic framework (MOF) with 1D nanotube channels has been constructed. The charge and size dependent ion-exchange of cationic dyes was investigated. Rho@1 could be used as a dual-emitting fluorescent sensor for sensing explosives by self-referencing energy transfer behaviors. [ABSTRACT FROM AUTHOR]

The first polyoxometalate-based metal–organic nanotube constructed via covalent bonds has been synthesized. POM anions stick the metal–organic nanotubes to build 3D nanotubular arrays. The stability, magnetic and proton conducting properties are investigated. [ABSTRACT FROM AUTHOR]

A unique cationic metal–organic framework was synthesized by connecting the neutral rod-shaped secondary building unit with a cationic dicarboxylate ligand. This framework showed a rare snub square tessellation pattern by the periodic tiling of triangular and square nanotubes. The charge- and size-dependent ion-exchange of anion dyes was investigated. [ABSTRACT FROM AUTHOR]

Two unprecedented tetrameric selenotungstates based on different Wells–Dawson-type fragments have been obtained: the {Sn7Se8W54} nanocluster exhibiting photocatalytic H2 evolution activity and the {Sn16Se11W56} chain, which are the first dimethyltin-functionalized selenotungstates reported and contain the unique {β-Se2W15} and {γ-Se2W14} building blocks, respectively. [ABSTRACT FROM AUTHOR]

Two novel open-chain carboxyethyltin decorated sandwich-type germanotungstates have been successfully synthesized. They could markedly increase the electrocatalytic activity of single-walled carbon nanotubes toward triiodide reduction when assembled into composite electrodes, which have shown a conversion efficiency of 6.32% that is comparable to that of Pt electrodes (6.29%) when used as counter electrodes in dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

An ultrastable [Ag55(MoO4)6]43+ ({Ag55Mo6} for short) nanocluster with a Ag-centered multishell structure in compound [Ag55(MoO4)6-(C≡CtBu)24(CH3COO)18](OAc)⋅2H2O (1) has been obtained. The ultrastability of 1 was demonstrated by Mulliken population analysis. In addition, the potential wide gap semiconductor property and electrochemical properties of 1 were investigated. [ABSTRACT FROM AUTHOR]

The AIE mechanism for cationic Ir(III) complexes with triazole-pyridine ligands has been determined by the combination of an experimental and a computational study. Larger structural relaxation and weak emissive excited-state intraligand charge transfer (ILCT) characters are responsible for the non-emission in solution, whereas the non-radiative processes are efficiently restricted in the solid state, enhancing the emission. [ABSTRACT FROM AUTHOR]

The structure of a recently-published metal–organic framework is deconstructed into its underlying net which is found to be of exceptional complexity. It is shown that this is because of local pentagonal symmetry and the structure is in fact the simplest possible (minimal transitivity) given that local symmetry. [ABSTRACT FROM AUTHOR]

Retraction of 'Sublimable cationic Ir(III) phosphor using chlorine as a counterion for high-performance monochromatic and white OLEDs' by Lei Ding et al., Chem. Commun., 2018, 54, 11761–11764. [ABSTRACT FROM AUTHOR]

Two Fe-substituted Dawson-type nanoscale selenotungstate clusters, {Fe6Se6W34} and {Fe10Se8W62} involving {α-Se2W14} and {γ-Se2W14} building blocks, have been isolated, which exhibit photocatalytic H2 evolution activity. Their electrochemical behaviours and magnetic properties were also investigated. [ABSTRACT FROM AUTHOR]