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1.
Dalton Trans ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129387

RESUMO

A series of host-guest materials containing polyoxometalate anions and lanthanide-organic layers have been synthesized and structurally characterized. By anion-π interactions between the anions and the π-acidic naphthalenediimide moieties, the materials emit strong red room-temperature phosphorescence and exhibit reversible photochromism.

2.
Chem Commun (Camb) ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32003370

RESUMO

Anionic POMs prefer to bond with positive metal cations instead of neutral or negative organic ligands. Therefore, it is challenging to synthesize POM-based MOFs, let alone bi-POM-based host-guest MOFs. In this work, an unprecedented bi-POM-based host-guest MOF, Na[Ni(enMe)2]4[Ni(enMe)2(H2O)2]2{[Ni6(µ3-OH)3(enMe)3 (SIP)1.5(B-α-PW9O34)]2[H3PNiW11O40]}·5enMe·33H2O (1), with Ni6-capped [PW9O34] as the node of the host framework and Keggin-type [PNiW11O40] units as the guest was synthesized. 1 showed excellent chemical stability towards aqueous solutions of pH 2-12 at both ambient and boiling temperature, providing opportunities for its application in fresh water harvesting from air.

3.
Small ; 15(45): e1903270, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31535783

RESUMO

Metal-free ultralong organic phosphorescence (UOP) materials have attracted significant attention owing to their anomalous photophysical properties and potential applications in various fields. Here, three pyrimidine-based organic luminogens, 9-(pyrimidin-2-yl)-9H-carbazole, 9-(4,6-dimethylpyrimidin-2-yl)-9H-carbazole, and 9-(5-bromopyrimidin-2-yl)-9H-carbazole are designed and synthesized, which show efficient yellow UOP with the longest lifetimes up to 1.37 s and the highest absolute phosphorescence quantum yields up to 23.6% under ambient conditions. Theoretical calculations, crystal structures, and photophysical properties of these compounds reveal that intramolecular hydrogen bonding, intermolecular π-π interactions, and intermolecular electronic coupling are responsible for forming dimers and generating highly efficient UOP. Their efficacy as solid materials for data encryption is demonstrated.

4.
Acta Crystallogr C Struct Chem ; 75(Pt 8): 1128-1133, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31380795

RESUMO

Noncovalent interactions, such as π-π stacking interactions, C-H...π interactions and hydrogen bonding, are important driving forces for self-assembly in the construction of functional supermolecules and materials, especially in multicomponent supramolecular systems. Herein, a novel compound based on a π-acidic naphthalene diimide derivative and a double hydroxide-bridged dinuclear Al3+ aqua ion cluster, namely bis[N,N'-bis(2-sulfonatoethyl)-1,4,5,8-naphthalene diimide] di-µ-hydroxido-bis[tetraaquaaluminium(III)] tetrahydrate, (C18H12N2O10S2)2[Al2(OH)2(H2O)8]·4H2O, was obtained using the above-mentioned common noncovalent interactions, as well as uncommon lone-pair-π interactions. Functional molecular modules were connected by these noncovalent interactions to generate obvious photochromic properties. The compound was prepared by the self-assembly of N,N'-bis(2-sulfoethyl)-1,4,5,8-naphthalene diimide and Al(NO3)3·9H2O under mixed solvothermal conditions, and was characterized in detail by single-crystal X-ray diffraction, powder X-ray diffraction and FT-IR spectroscopy. The thermal stability and photochromic properties were also investigated; furthermore, in-situ solid-state UV-Vis absorption spectroscopy and electron spin resonance (ESR) were used to clarify the photochromic mechanism.

5.
Dalton Trans ; 48(29): 10790-10794, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31246197

RESUMO

Luminescent Cu(i) iodide complexes featuring simple neutral diimine and phosphine ligands were prepared. The emission intensity of these complexes was significantly enhanced by crystallization. Intermolecular π-π interactions between the adjacent diimine ligands should be responsible for the crystallization-induced emission enhancement (CIEE) behaviors through consolidating the structural rigidity of these complexes.

6.
Dalton Trans ; 48(27): 9930-9934, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31197290

RESUMO

A Ho-MOF ([Ho(SIP)(H2O)5]·3H2O (1), NaH2SIP = monosodium 5-sulfoisophthalic acid) was designed and synthesized for proton conductivity. It showed a proton conductivity of 8.2 × 10-4 S cm-1 at 343 K and 98% relative humidity. Besides, compound 1 showed excellent water and chemical stability as well as reversible dehydration and hydration closely related to the proton conductivity.

7.
Chem Commun (Camb) ; 55(11): 1643-1646, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30657485

RESUMO

A sextuple ordered interpenetrated copper-naphthalenediimide network has been constructed by combining the features of porous metal-organic frameworks and π-conjugated supramolecular aggregation. The material exhibits intrinsic semiconductive features with narrow bandgap energy (1.2 eV) and outstanding electron transport. Theoretical calculations combined with experiments indicate that the high electron conduction may originate from π-d coupling and J-aggregation.

8.
Dalton Trans ; 48(4): 1418-1426, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30628618

RESUMO

Two emissive copper(i) halide complexes (PNNP)Cu2Br2 (1) and (PNNP)Cu2I2 (2), which are constructed from butterfly-shaped dinuclear Cu2X2 cores and a new tetradentate ligand (PNNP = 1,3-bis(1-(2-(diphenylphosphanyl)phenyl)-1H-pyrazol-3-yl)benzene), were synthesized and characterized. These chelates exhibit bright green (λmax = 517 nm, 1) and bluish-green (λmax = 492 nm, 2) photoluminescence in the solid state with quantum yields of 42% (1) and 58% (2), and lifetimes of 13 µs (1) and 8.8 µs (2) at room temperature. Computational density functional theory/time-dependent density functional theory (DFT/TDDFT) calculations were performed to elucidate the nature of their electronic transitions and to predict their detailed photophysical properties. The results of DFT/TDDFT calculations, combined with the temperature dependence of spectroscopic properties and emission decay behaviors, suggest that the emission in the solid state originates from the 1,3(MLCT + XLCT + ILCT) excited states, which are in thermal equilibrium with small energy differences of about 0.1 eV. A comparative study of the titled complexes reveals that the emissive-state characteristics and photophysical properties of these complexes are significantly affected by the ligand field strength and atomic number of the halogen atom, as well as by the percentage of the XLCT transition involved in the lowest excited states. Compared with its bromide counterpart (1), the iodide complex (2) shows a much higher phosphorescence quantum yield (0.94 vs. 0.50), a much shorter phosphorescence decay time (58 µs vs. 274 µs), a much larger phosphorescence rate constant (1.6 × 104 s-1vs. 1.8 × 103 s-1), and a larger phosphorescence contribution (25% vs. 8%) in room-temperature emission, due to the more efficient spin-orbit coupling (SOC).

9.
Dalton Trans ; 48(4): 1179-1183, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30570627

RESUMO

A novel cuprous complex bearing two functional parts, i.e. a luminophoric part and a structural part, exhibits distinct luminescence responses to a variety of volatile organic compounds of different polarities in the solid state.

10.
Chemistry ; 24(41): 10498-10502, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-29740893

RESUMO

Room-temperature phosphorescence (RTP) was realized for the first time in a polyoxometalate-based charge-transfer (CT) hybrid material bearing polyoxometalates (POMs) as electron-donors (D) and rigid naphthalene diimides (NDIs) as electron-acceptors (A), meanwhile, this hybrid material displayed photochromism as well. The significant D-A anion-π interaction induced an additional through-space charge-transfer pathway. The resulting suitable D-A CT states can efficiently bridge the relatively large energy gap between the NDI-localized 1 π-π* and 3 π-π* states and thus trigger the ligand-localized phosphorescence (3 π-π*).

11.
Dalton Trans ; 47(17): 5956-5960, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29666869

RESUMO

A novel tetranuclear Ag(i) complex, [Ag4(µ-DMPTP)2(POP)3][BF4]2 (Ag4N2P3), has been designed to achieve highly efficient thermally activated delayed fluorescence (TADF). Photophysical investigations show that the compound exhibits highly efficient TADF (Φ = 76%) and has a very short ambient-temperature TADF decay time of only 0.65 µs, corresponding to a radiative decay rate of k = Φ/τ = 1.2 × 106 s-1, a value belonging to the fast radiative rates in TADF materials.

12.
Dalton Trans ; 47(6): 1796-1800, 2018 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-29354842

RESUMO

A trigonal propeller-shaped hybrid polyoxometalate (POM) (NH2Me2)3{[Nd(Mo4O13)(DMF)4]3(BTC)2}·8DMF (1; BTC = 1,3,5-benzenetricarboxylate) has been synthesized and structurally characterized. The planar {Mo4} segment is tailored from the precursor Lindqvist polyoxoanion [Mo6O19]2- firstly, and plays a key role in the reassembly of 1. Furthermore, the magnetic studies reveal that 1 shows single-molecule magnet (SMM) behavior.

13.
Dalton Trans ; 47(4): 1027-1031, 2018 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-29271439

RESUMO

Utilizing metal-ligand binding as the driving force, a unique photochromic hydrogel cross-linked by metal ions and π-acidic naphthalene bisimide dyes was obtained by simply mixing a two-phase solution. The mechanism of the coordination-driven self-assembly is elucidated by the morphological, XRD, FT-IR, ESR, UV-Vis and TGA studies and the controlled experiments.

14.
Angew Chem Int Ed Engl ; 56(47): 15006-15009, 2017 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-28990260

RESUMO

Two efficient blue thermally activated delayed fluorescence compounds, B-oCz and B-oTC, composed of ortho-donor (D)-acceptor (A) arrangement were designed and synthesized. The significant intramolecular D-A interactions induce a combined charge transfer pathway and thus achieve small ΔEST and high efficiencies. The concentration quenching can be effectively inhibited in films of these compounds. The blue non-doped organic light emitting diodes (OLEDs) based on B-oTC prepared from solution processes shows record-high external quantum efficiency (EQE) of 19.1 %.

15.
Chem Commun (Camb) ; 53(70): 9701-9704, 2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28776615

RESUMO

Lone pair-π interaction-induced charge-transfer was successfully used for switching the conductance of a coordination network, through variation of the degree of charge transfer caused by external photostimulation. The underlying mechanism is attributed to the changes in efficient charge-carriers by photoinduced strong charge transfer, which was investigated by in situ UV-Vis absorption, ESR, and computational studies.

16.
Dalton Trans ; 46(15): 4898-4901, 2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28317991

RESUMO

The first visible-light-responsive photochromic polyoxometalate-templated lanthanide-organic framework (LOF) has been constructed from a carboxyphenyl-substituted naphthalenediimide (NDI) derivative, which displays an unusual four-fold interpenetration of an srs topological network, featuring a variety of anion-π interactions between polyoxoanions and π-acidic NDI moieties, and undergoes a rapid reversible photochromic transformation upon blue light irradiation.

17.
Inorg Chem ; 55(19): 9528-9536, 2016 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-27652823

RESUMO

A series of highly emissive neutral dinuclear silver complexes [Ag(PPh3)(X)]2(tpbz) (tpbz = 1,2,4,5-tetrakis(diphenylphosphanyl)benzene; X = Cl (1), Br (2), I (3)) was synthesized and structurally characterized. In the complexes, the silver atoms with tetradedral geometry are bridged by the tpbz ligand, and the ends of the molecules are coordinated by a halogen anion and a terminal triphenylphosphine ligand for each silver atom. These complexes exhibit intense white-blue (λmax = 475 nm (1) and 471 nm (2)) and green (λmax = 495 nm (3)) photoluminescence in the solid state with quantum yields of up to 98% (1) and emissive decay rates of up to 3.3 × 105 s-1 (1) at 298 K. With temperature decreasing from 298 to 77 K, a red shift of the emission maximum by 9 nm for all these complexes is observed. The temperature dependence of the luminescence for complex 1 in solid state indicates that the emission originates from two thermally equilibrated charge transfer (CT) excited states and exhibits highly efficient thermally activated delayed fluorescence (TADF) at ambient temperature. At 77 K, the decay time is 638 µs, indicating that the emission is mainly from a triplet state (T1 state). With temperature increasing from 77 to 298 K, a significant decrease of the emissive decay time by a factor of almost 210 is observed, and at 298 K, the decay time is 3.0 µs. The remarkable decrease of the decay time indicates that thermal population of a short-lived singlet state (S1 state) increases as the temperature increases. The charge transfer character of the excited states and TADF behavior of the complexes are interrogated by DFT and TDDFT calculations. The computational results demonstrate that the origin of TADF can be ascribed to 1,3(ILCT + XLCT+ MLCT) states in complexes 1 and 2 and 1,3(XLCT) states mixed with minor contributions of MLCT and ILCT in complex 3.

18.
Chemistry ; 22(32): 11283-90, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27376623

RESUMO

Hydrophobic metal-organic frameworks (MOFs) not only have high water stability, but also exhibit high adsorption capacity towards organic molecules, in particular hydrocarbons. Herein we report a rare metal fluoride organic framework MFOF-1 with high hydrophobicity, which is constructed from unprecedented fluoride- and sulfate-bridged cubane-type tetranuclear cobalt clusters. MFOF-1 consists of three types of polyhedral cages with face-sharing configurations, and possesses a novel (3,9)-connected 3D+3D→3D self-interpenetrating array or the rare pyr topology. MFOF-1 shows high thermal stability and high stability in water and even acid/base aqueous solutions, and exhibits rather high H2 and CO2 storage capacities at ambient pressure. Remarkably, MFOF-1 shows little adsorption of water but considerably high uptakes of methanol, n-hexane, cyclohexane, and benzene, and exhibits a certain degree of adsorption selectivity of benzene over cyclohexane.

19.
Inorg Chem ; 55(15): 7467-75, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27404980

RESUMO

Two mononuclear cuprous complexes [Cu(PNNA)(POP)]BF4 (1) and [Cu(PNNA)(Xantphos)]BF4 (2) (PNNA = 9,9-dimethyl-10-(6-(3-phenyl-1H-pyrazol-1-yl)pyridin-3-yl)-9,10-dihydroacridine, POP = bis[2-(dipenylphosphino)phenyl]ether, Xantphos =4,5-bis(diphenylphosphino)-9,9-dimethylxanthene), with intense bluish-green luminescence based on a new diimine ligand were designed and synthesized. Their structural, electrochemical, and photophysical properties were characterized by single-crystal X-ray analysis, cyclic voltammetry, temperature dependence of spectroscopy, time-dependent emission spectroscopy, etc. The complexes exhibit high photoluminescence quantum yields in doped films (up to 74.6%) at room temperature. Thermally activated delayed fluorescence based on intraligand charge transfer was observed by grafting a strong electron-donor moiety, 9,9-dimethylacridan, on the diimine ligand, which is supported by the density functional theory calculations on two complexes. Highly efficient solution-processed OLEDs based on these two complexes were fabricated, among which the electroluminescent device using 2 as dopant shows a peak external quantum efficiency of 7.42%, a peak current efficiency of 20.24 cd/A, and a maximum brightness of 5579 cd/m(2).

20.
Chem Commun (Camb) ; 52(46): 7394-7, 2016 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-27192943

RESUMO

An unusual room-temperature light sensitivity was realized in a polyoxometalate-based hybrid material due to cooperative multicomponent molecular charge-transfer interactions taking place in this material, mainly among POMs, NDIs, and other molecules. The functional π-acidic NDI linkers and POM clusters in the discussed hybrid material were individually designed as photosensors and electron reservoirs. To propose a photo-induced charge-transfer mechanism, EPR, XPS, UV-Vis and computational studies were carried out, and indicated the presence of active charge-transfer interactions among several of the components.

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