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We have constructed a novel porous pyrene-based organic cage, PyTC1, through the condensation reaction of cyclohexanediamine with 5,5′-(pyrene-1,6-diyl)diisophthalaldehyde. Single-crystal X-ray dif...

Based on ship navigational requirements and safety in foggy conditions and with a particular emphasis on avoiding ship collisions and improving navigational abilities, we constructed a fog navigation dataset along with a new method for enhancing foggy images and perceived visibility using a discriminant deep learning architecture and the EfficientNet neural network by replacing the SE module and incorporating a convolution block attention module and focal loss function. The accuracy of our model exceeded 95%, which meets the needs of an intelligent ship navigation environment in foggy conditions. As part of our research, we also determined the best enhancement algorithm for each type of fog according to its classification.

The detailed mechanism reveals the deep relationship of reaction activity with acidity, substituent nature (at position 1 or 2), and conformation in CO2 reduction.

Responsive materials have received much attention due to modulated properties under stimuli such as light, heat, and electricity. A photoresponsive porous molecular crystal (

Covalent organic frameworks (COFs) are promising crystalline materials for photocatalytic solar- to hydrogen-energy conversion due to the tunable chemical structures and energy band gaps. Herein, we report a chemical modification strategy for improving the photocatalytic activity of COFs. A benzene-1,3,5-tricarbaldehyde (BT)- and benzothiadiazole derivative-based two-dimensional donor-acceptor (D-A) COF, denoted as BT-COF, were fabricated and further modified by using an alternative electron-donating unit, 2-hydroxybenzene-1,3,5-tricarbaldehyde (HBT), to the polycondensation reaction, yielding HBT-COF with an enhanced internal D-A effect and hydrophilicity. Interestingly, the photocatalytic H2 production rate of HBT-COF reaches 19.00 μmol h-1, which is 5 times higher than that of BT-COF (3.40 μmol h-1) under visible light irradiation. The increase in photocatalytic activity of HBT-COF is rationally attributed to finely tuned energy levels and improved wettability, which in turn leads to broadened visible light absorption, efficient photoinduced charge separation and transfer, and enhanced interactions between the COF catalyst and reaction substrates. The present results demonstrate that a subtle structural modification can significantly modulate the band structure and interfacial property, thus providing a feasible strategy for the optimization of COF-based photocatalytic systems.

In order to solve the problem of uncontrollable cutting depth and the rough incision edge of the cornea with manual trephine in lamellar keratoplasty, an ultrasonic‐assisted corneal trephination method has been proposed for the first time in accordance with the advantage of ultrasonic vibration cutting, and the corresponding robotic system has been designed and researched. According to the traditional process of lamellar keratoplasty, the requirements of the surgical robotic system were first proposed. On this basis, the robotic system was designed and its schematic diagram was introduced. Second, the key components of the robotic body such as the eccentric adjusting mechanism and the end‐effector of ultrasonic scalpel were illustrated, which can realise corneal trephination of different incision diameters without scalpel replacement. Then the operation flow chart of a robot‐assisted lamellar keratoplasty was put forward. Finally, the preliminary verified experiments were performed using a grape and a porcine eyeball, respectively, in vitro with the prototype system. The results show that the robotic system can basically satisfy the operation requirements of lamellar keratoplasty. Owing to the less cutting force and smoother corneal incision edge of ultrasonic‐assisted lamellar keratoplasty compared with manual trephine, it was proved to be more feasible and superior.

Nanotubes with circularly polarized luminescence (CPL) are attracting much attention due to many potential applications, such as chiroptical materials, displays, and sensing. However, it remains a challenge to change the assemblies of ordinarily molecular building blocks into CPL supramolecular nanotubes. Herein, the regulation of quite common dipeptide (Fmoc-FF) assemblies into unprecedented helical nanotubes exhibiting intense CPL is reported by simply doping a few phthalocyanine (octakis(carboxyl)phthalocyaninato zinc complex (Pc)) molecules. Interestingly, altering the Fmoc-FF/Pc molar ratios over a wide range cannot change the nanotubes structures according to transmission electron microscopy (TEM) and atomic force microscope (AFM) measurements. Although molecular dynamics simulations suggest that the noncovalent interactions between Fmoc-FF and Pc are quite weak, few Pc molecules can still change the secondary structures of a large number of Fmoc-FF assemblies, which hierarchically form helical supramolecular nanotubes with long-range ordered molecular packing, leading to intense CPL signals with large luminescence dissymmetry factor (glum = 0.04). Consequently, the chiral reorganization of Fmoc-FF assemblies is dependent on the coassembly between Pc molecule and Fmoc-FF supramolecular architectures. These results open the possibility for the fine-tuning of helix and supramolecular nanotubes with CPL properties by using a small number of cofactors.

The functionalization of natural 1D architectures is dependent on hierarchically inner nanostructures. However, the artificial supramolecular nanofibers or nanotubes were rarely developed with complex inner structures. Inspired by a biomimetic strategy, single-molecule-diameter nanofibers of double-decker phthalocyanine (EuPc2) with compartmentalized internal space and fantastic electrochemical features were developed upon air/water interfacial assembly with poly-l-lysine. EuPc2/poly-l-lysine nanofibers can be electrochemical sensors both in water and the gas phase and have the best analytical performances for nitrite among all the porphyrins or phthalocyanines monomers and assemblies. Imbedding nitrite in compartments not only promotes the sensing but also changes the supramolecular chirality of nanofibers, and the morphological-dependent sensing properties of EuPc2 assemblies in water are different from that in the gas phase. These results suggest the unprecedented properties for diverse applications of artificial 1D architectures containing complex inner nanostructures.

The imine condensation reaction of 5,5'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalaldehyde with cyclohexanediamine resulted in a shape-persistent multifunctional tubular organic cage (MTC1). It exhibits selective fluorescence sensing towards divalent Pd ions with a very low detection limit (38 ppb), suggesting effective complexation between these two species. Subsequent reduction of MTC1 and Pd(OAc)2 with NaBH4 afforded a cage-supported catalyst with well-dispersed ultrafine Pd nanoparticles (NPs) in a narrow size distribution (1.9±0.4 nm), denoted as Pd@MTC1-1/5. Such ultrafine Pd NPs in Pd@MTC1-1/5, in cooperation with photocatalytically active MTC1, enable efficient sequential reactions involving visible light-induced aerobic hydroxylation of 4-nitrophenylboronic acid to 4-nitrophenol and the following hydride reduction with NaBH4 . This is the first example of a multifunctional organic cage capable of sensing, directing nanoparticle growth, and catalyzing sequential reactions.

Fabricating ultrathin two-dimensional (2D) covalent organic framework (COF) nanosheets (NSs) in large scale and high yield still remains a great challenge. This limits the exploration of the unique...

Hydrogen-bonded organic framework (HOF)-based catalysts still remain unreported thus far due to their relatively weak stability. In the present work, a robust porous HOF (HOF-19) with a Brunauer–Emmett–Teller surface area of 685 m(2) g(−1) was reticulated from a cagelike building block, amino-substituted bis(tetraoxacalix[2]arene[2]triazine), depending on the hydrogen bonding with the help of π−π interactions. The postsynthetic metalation of HOF-19 with palladium acetate afforded a palladium(II)-containing heterogeneous catalyst with porous hydrogen-bonded structure retained, which exhibits excellent catalytic performance for the Suzuki–Miyaura coupling reaction with the high isolation yields (96−98%), prominent stability, and good selectivity. More importantly, by simple recrystallization, the catalytic activity of deactivated species can be recovered from the isolation yield 46% to 92% for 4-bromobenzonitrile conversion at the same conditions, revealing the great application potentials of HOF-based catalysts.

We report here the electrochemical reaction mechanism of CO2 reduction catalyzed by aminopyridine cobalt complex. The thermodynamic energy barriers and the rate-determining step are unveiled on the basis of DFT calculation results. In addition, a computational investigation for the purpose of predicting the catalytic reactivity of a series of aminopyridine metal (Mn, Ni, Cr) complexes has also been carried out. The compound with Cr as central metal exhibits a low energy barrier in the rate-determining step. On the other hand, the electron-donating substituents are revealed to be able to reduce the energy barrier of the rate-determining step by increasing the eletrophilicity of the oxygen atom in C-OH moiety. Furthermore, the compounds with π-π conjugation in meso-positions cannot adsorb the CO2 molecule and therefore do not show catalytic activity for CO2 reduction. In contrast, the compounds with p-π conjugation in meso-positions exhibit a good catalytic activity for the reduction of CO2.

The Raman spectra of the mixed (naphthalocyaninato)[tetrakis(4-[Formula: see text]-butylphenyl)porphyrinato] rare earth double-decker compounds M(Nc)(TBPP) (M = Y, La, Ce, Eu, Dy, Lu) were studied with Density Functional Theory for the first time. The results reveal the fingerprint band for naphthalocyanine to be around 1455–1615 cm[Formula: see text] and porphyrin around 693–749 cm[Formula: see text]. Coupled Nc–Por ring–ring interaction vibration modes are also detected at 1470–1522 cm[Formula: see text], owing to the stretching between the central metal and the N atoms. These vibration modes are recognized as the dominating components in the Raman spectra of those double-decker compounds.

Incorporation of the dimeric phthalocyanine into sandwich phthalocyaninato europium framework extends the conjugated electronic molecular structure and optimizes the ambipolar semiconducting properties of the QLS thin film-based OFET device, resulting in a significant increase in the hole and electron mobilities from 4.30 × 10−7 and 0.70 × 10−7 cm2 V−1 s−1 for monomeric phthalocyanine-containing triple-decker Eu2[Pc(SC6H13)8]3 (1) to 0.07 and 0.06 cm2 V−1 s−1 for the dimeric phthalocyanine-containing quintuple-decker [Pc(SC6H13)8]2Eu2[BiPc(SC6H13)12]Eu2[Pc(SC6H13)8]2 (2). This in turn induces an enhanced gas sensing detection performance for NO2 with the sensitivity increasing from 23.4% for 1 to 46.7% ppm−1 for 2. The present result appears interesting in terms of improving the gas-sensing properties of phthalocyanine-based molecular materials via molecular design and synthesis rather than tuning the film morphology.

Metal–organic framework (MOF) nanosheets are a new type of two-dimensional nanomaterial. Their properties and performances are expected to correlate strongly with the sheet structure, particularly the number of layers (sheet thickness). Yet, synthetically controlling the layer number at the molecular scale is highly difficult. Herein, a facile method is introduced to fabricate substrate-supported MOF nanosheets with precisely controllable layer numbers, using the Langmuir–Blodgett technique. Large-area, porous, and uniform MOF nanosheets, based on 5,10,15,20-tetrakis[4′-(terpyridinyl)phenyl]porphyrin-cobalt(II) (Co-TTPP) coordination polymer, were constructed and characterized in detail by atomic force microscopy, transmission electron microscopy, energy dispersive spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, and a photoelectronic conversion technique. As a prototype sensor device, a series of substrate-supported Co-TTPP nanosheets was further investigated for the fluorescence detection of DNA towards rapid clinical diagnosis. The ten-layer Co-TTPP nanosheet exhibits an impressive performance with a very low detection limit of ca. 0.1 nM, outstanding specificity, and multiplexed DNA detection, comparable to some top-notch free-standing nanomaterial sensors. Importantly, our results also revealed the synergistic contributions of suitable pore size and optimal layer number of the Co-TTPP nanosheet for highly efficient DNA detection for the first time.

Organic field effect transistor (OFET) devices fabricated based on triple-decker mixed-(phthalocyaninato)(porphyrinato) yttrium(III) and fullerene cocrystals show high carrier mobilities of 3.72 and 2.22 cm2 V−1 s−1 for holes and electrons, respectively, at the interface of cocrystallized supramolecular layers, representing one of the most excellent cocrystal ambipolar OFET devices reported thus far.

It is a significant challenge to develop a high-efficiency synthetic methodology to access fully conjugated 2D conjugated polymer (CP)/covalent organic framework (COF) nanosheets (NSs) that have great application potential for electronics and energy. Herein, we report the exfoliation of a series of amorphous ethynyl-linked phthalocyanine (Pc) CPs (MPc-CPs, M = Fe, Co, Fe0.5Co0.5) into ultrathin MPc-CP NSs. Random coupling between the four regioisomers (with D4h, D2h, C2v and Cs symmetry) of the two tetra-β-substituted phthalocyanine precursors endows the resulting phthalocyanine conjugated polymers MPc-CPs with intrinsic structural defects and a disordered framework on individual layers. This in turn induces a diminished interlayer overlapping and a weakened interlayer π–π stacking interaction, facilitating the possible exfoliation of MPc-CPs into ultrathin 2D NSs with a yield of over 50%. The direction observation by transmission electron microscopy (TEM) and atomic force microscopy (AFM) demonstrates that the ultrathin MPc-CP NSs possess a smooth surface with a uniform thickness of 1–3 nm and a lateral size of hundreds of nanometers. The as-prepared bimetallic Fe0.5Co0.5Pc-CP NSs were further used to fabricate a heterostructure Fe0.5Co0.5Pc-CP NS@G with graphene NSs as an oxygen reduction reaction (ORR) catalyst, which exhibits an onset potential of 1006 mV and a half-wave potential of 927 mV in 0.1 M KOH, representing one of the best values in an alkaline medium. Moreover, the excellent ORR activity of the exfoliated tetrapyrrole-based conjugated NSs hybridized with graphene has also been demonstrated by a Zn–air battery device, showing an open circuit voltage of 1.34 V and a peak power density of ca. 180 mW cm−2.

We report here a stable rare zirconium metal–organic framework (MOF) exhibiting a sky topology, Zr6(μ3-O)4(μ3-OH)4(ITTC)4 (UPC-158) (where H3ITTC = 4,4′,4′′-(1H-imidazole-2,4,5-triyl)tribenzoic acid), established by Zr6(μ3-O)4(μ3-OH)4(−COO)12 clusters and 4,4′,4′′-(1H-imidazole-2,4,5-triyl)tribenzoic acid with abundant π-electrons as an ideal material for removing iodine vapor – a major radioactive fission waste. The iodine adsorption efficiency of the acid-treated UPC-158-HX series shows a substantial improvement compared with that of the parental UPC-158 (1.77 g g−1), and the iodine vapor uptake of 2.92 g g−1 at 343.15 K for UPC-158-HCl has reached the maximum value among the reported MOF materials. In addition, the protonation and deprotonation of imidazole nitrogen alter the symmetry of internal structures, resulting in a strong fluorescence enhancement of the material in the pH range of 10–11, making it a potentially precise pH meter. This work not only provides insights into the discovery of unprecedented structures and topologies through the rational choice of organic linkers via experimental and simulation methods but also paves the way to understand the structure related functional applications. It also opens up a window for the design and construction of highly complex porous and stable structures for sophisticated applications.

An interaction between a mixed (phthalocyaninato)(porphyrinato) yttrium triple-decker and a fullerene in the solution state together with the solid state is clearly revealed by 1H NMR, electronic absorption and luminescence spectroscopy, single crystal X-ray diffraction analysis results and DFT calculations. The close interface between a sandwich-type tetrapyrrole rare earth triple-decker and a fullerene in cocrystals affords stronger charge transfer (CT) and thus a more effective photoelectric conversion response than each individual.

Sonogashira–Hagihara coupling reaction of photoswitchable dithienylethene (AEDTE) with metal-free 5,10,15,20-tetrakis(4-iodophenyl)porphyrin and its metal derivatives (MTIPP, M = H2, Zn(II), Fe(II)...

The investigation on the catalytic properties of porous organic cages is still in an initial stage. Herein, the reaction of cyclohexanediamine with 5,15-di[3’,5’-diformyl(1,1’-biphenyl)]porphyrin affords a porphyrin tubular organic cage, PTC-1(2H). Transient absorption spectroscopy in solution reveals much prolonged triplet lifetime of PTC-1(2H) relative to monomer reference, illustrating the unique photophysical behavior of cagelike photosensitizer. The long triplet lifetime ensures high-efficiency singlet oxygen evolution according to homogeneous photo-bleach experiment, electron spin-resonance spectroscopy, and aerobic photo-oxidation of benzylamine. Furthermore, microporous supramolecular framework of PTC-1(2H) is able to promote the heterogeneous photo-oxidation of various primary amines with conversion efficiency above 99% under visible light irradiation. These results indicate the great application potentials of porous organic cages in heterogeneous phase., The investigation on the catalytic properties of porous organic cages is still in an initial stage. Herein, the heterogeneous photocatalytic superiority of microporous porphyrin organic cage has been clearly elucidated due to unique cage-induced long triplet lifetime and porous structure.

The infrared spectra of tetrakis(dibutylamino) phthalocyanine and octakis(dibutylamino) compounds were studied via theoretical investigations. The results reveal deep fusion of the peripheral alkylamino moieties with the phthalocyanine chromophore in the tetrakis(dibutylamino)- but not in the octakis(dibutylamino)-phthalocyanine compounds. The successive localized molecular orbitals (LMO) and bond order analyses give support for the infrared vibrational results.

A hierarchical microporous graphitic carbon material intrinsically doped with sulfur and extrinsically doped with dual cobalt species [Co3O4 and Co(PO3)2, termed as CoOP] nanoparticles was prepared from a sustainable waste biomass, peanut shell, with CO2 gas as the activating agent through a thermal-reduction method. The resulting CoOP@bio-C exhibits an overall superior ORR catalytic activity, stability and resistance to methanol crossover in alkaline media to commercial Pt/C, with onset and half-wave potentials of 0.91 and 0.81 V in 0.1 M KOH, a limiting current density of −5.7 mA cm−2, and a small Tafel slope of 57 mV dec−1, representing the best result among the biomass-based carbon electrocatalysts. In particular, comparative studies reveal the significant effect of the work function of corresponding catalytic materials on the ORR electrocatalysis. Dual-doped CoOP@bio-C with a work function of 5.42 eV, closer to that of Pt (5.65 eV), displays much better electrocatalytic activity than single-doped Co3O4@bio-C, single-doped Co(PO3)2@bio-C and bio-C-800 catalysts with work functions of 8.35, 6.61 and 5.02 eV, respectively, due to its good adsorption nature to O2 and desorption nature to the reaction intermediates. The present result will be surely helpful for the design and synthesis of biomass resource-based ORR catalysts with great application potential.

Mixed phthalocyanine-porphyrin-based conjugated microporous polymers (CMPs) are still rare, limited to one sole NN-bridged example. Developing new mixed phthalocyanine-porphyrin-based CMP compounds towards exploring their new functionalities and application potential is therefore of significant importance. In the present case, four ethynyl-linked mixed phthalocyanine-porphyrin-based 2D CMPs, including FePcZnPor-CMP, ZnPcFePor-CMP, FePcFePor-CMP, and ZnPcZnPor-CMP, were fabricated by utilizing a Sonogashira–Hagihara coupling reaction. A series of spectroscopic and electron microscopy methods confirmed the successful fabrication of the as-prepared CMPs with alternate distribution of phthalocyanine and porphyrin chromophores. The electrocatalytic activity of these CMPs for the oxygen reduction reaction (ORR) was evaluated by cyclic voltammetry, rotating disk electrode, and rotating ring-disk electrode tests. In alkaline media, the two FePc-containing CMPs exhibit excellent ORR catalytic activity with an E1/2 as high as 863–866 mV, making them significantly superior to FePor-containing catalyst ZnPcFePor-CMP and comparable to commercial Pt/C. On the basis of the experimental results and theoretical calculations, the significantly higher ORR performance of the two FePc-containing CMPs than the FePor-containing catalyst ZnPcFePor-CMP originates from the stronger coordination field of the phthalocyanine macrocyclic ligand than porphyrin, which is more favorable for stabilizing Fe2+ species.

The location of the unpaired electron in neutral bis(phthalocyaninato) yttrium double-decker complexes, with different substituents, has been studied on the basis of both experimental methods and density functional theory (DFT) calculations over the molecular structures, atomic charges, electronic absorption, infrared spectra, and electron paramagnetic resonance. The results reveal the location of the unpaired electron mainly on the carbon atoms of both tetrapyrrole chromophores with the population distribution obviously affected by the peripheral substituents.

Bulky and strong electron-donating dibutylamino groups were incorporated onto the peripheral positions of one of the two phthalocyanine ligands in the bis(phthalocyaninato) terbium complex, resulting in the isolation of heteroleptic double-decker (Pc)Tb{Pc[N(C4H9)2]8} {Pc = phthalocyaninate; Pc[N(C4H9)2]8 = 2,3,9,10,16,17,23,24-octakis(dibutylamino)phthalocyaninate} with the nature of an unsymmetrical molecular structure, a square-antiprismatic coordination geometry, an intensified coordination field strength, and the presence of organic radical-f interaction. As a total result of all these factors, this sandwich-type tetrapyrrole lanthanide single-ion magnet (SIM) exhibits an overall enhanced magnetic performance including a high blocking temperature (TB) of 30 K and large effective spin-reversal energy barrier of Ueff = 939 K, rendering it the best sandwich-type tetrapyrrole lanthanide SIM reported thus far.

A systematic investigation over the formation mechanism of the subphthalocyanine, SubPc(Cl), with phthalonitrile as the initial reagent mediated by boron trichloride in the solvent of p-xylene has been carried out on the basis of density functional theory, revealing truly a long reaction pathway containing twenty-three elementary reactions. The calculation results well reproduce and rationalize the experimental findings including the selection of high boiling point reaction media of p-xylene, employment of excessive amount of BCl3 reagent, and liberation of Cl2 during the reaction process. In particular, the crucial catalytic nature of BCl3 has been clearly disclosed: in addition to activating the cyano groups, boron trichloride also works as chloride-transfer shuttle to prompt the reactions occurring and proceeding. The present result will put forwards the exploration over the formation mechanisms of phthalocyanines and porphyrins.

Two triple-decker dinuclear sandwich dysprosium complexes, which are represented as Dy2[Pc(OC5H11)8]2[Cor(FPh)3] (1) and Dy2[Pc(OC5H11)8]2[Cor(ClPh)3] (2), were synthesized and characterized by spectroscopic and electrochemical methods in nonaqueous media. Their electronic structures were also investigated on the basis of TD-DFT calculations. The sandwich triple-decker nature with the molecular conformation of [Pc(OC5H11)8]Dy[Cor(FPh)3]Dy[Pc(OC5H11)8] for compound 1 was unambiguously revealed by single-crystal X-ray diffraction analysis and showed each dyprosium ion to be octacoordinated by the isoindole and pyrrole nitrogen atoms of an outer phthalocyanine ring and the central corrole ring, respectively. In addition, the magnetic properties of both compounds have also been characterized for exploring the functionalities of these types of triple-decker complexes.

( R )-(+)- or ( S )-(−)-1,1′-bi-2-naphthol (BINOL) was applied as a remote chiral auxiliary to connect the two facing porphyrin rings, resulting in the BINOL-strapped chiral bis (porphyrinato) cerium double-decker complexes ( R )-/( S )- 1 and ( R )-/( S )- 2 , which were carefully characterized by a range of spectroscopic and electrochemical methods. Perfect mirror images were observed in their circular dichroism (CD) spectra with a negative sign in the Soret band for ( R )-enantiomers and a positive sign for ( S )-enantiomers, which suggests the C 2 -chirality of a BINOL strap is transcribed to the double-decker core as a defined chiral twist in the inter-porphyrin arrangement. Furthermore, the CD intensities of ( R )-/( S )- 1 are always larger than those of ( R )-/( S )- 2 , indicating that the intramolecular chirality transfer efficiency can be finely tuned by changing the length of interlocking moieties.

Novel chiral pyrene-binaphthalene compounds, ( R )-/( S )-(13Z,21bZ)-dinaphtho[2,1-e:1′,2′-g]pyreno[4,5-b][1,4]diazocine ( 1 ) and ( R )-/( S )-(3bZ,5Z,7Z,9Z,12bZ,14Z,16Z,18Z)-bis(dinaphtho[2,1-e:1′,2′-g])pyreno[4,5-b:9,10-b′]bis([1,4]diazocine) ( 2 ), were synthesized and characterized by a series of spectroscopic methods including MALDI-TOF mass, NMR, and electronic absorption methods. Their binaphthalene-linked pyrene nature has been unambiguously revealed on the basis of single crystal X-ray diffraction analysis of both ( R )- and ( S )- 1 . In addition, their electronic structure was also investigated on the basis of DFT calculations.

Herein, a density functional calculation method was used to explore the formation mechanism of a metal-free, homobinuclear phthalocyanine dimer. The result not only well rationalizes the Pc dimer formation starting from 1,2-diamino-9,10,16,17,23,24-hexa-(2,6-dimethylphenoxy)-tribenzotetrazaporphyrin (1-OR) through an intricate pathway but, more importantly, also predicts the formation of ammonia during the reaction process; this results in the successful experimental detection of NH4+ in the acidic reaction system. Further experimental efforts have facilitated the isolation of one of the theoretically revealed reaction intermediates di-[2-amino-7,8,14,15,21,22-hexa-(2,6-dimethylphenoxy)-tribenzotetrazaporphyrinato]-amine (9-OR); this indicates the significance of combining experimental with DFT calculation method towards clarifying the reaction mechanisms.

Strong electron-donating dialkylamino groups were incoporated onto the phthalocyanine ligand in bis(phthalocyaninato) rare earth complexes for the first time to investigate their effects on the spectroscopic properties, electrochemistry, and electronic structure. The bis[2,3,9,10,16,17,23,24-octakis(dibutylamino)phthalocyaninate] rare earth complexes M{Pc[N(C4H9)2]8}2 {Pc[N(C4H9)2]8 = 2,3,9,10,16,17,23,24-octakis(dibutylamino)phthalocyanine, M = Y, Tb} (1, 2) were isolated from the condensation reaction of the corresponding metal free ligand in a refluxing mixture of n-octanol/1,2,4-trichrolobenzene (TCB) (1 : 5) in the presence of M(acac)3·nH2O (M = Y, Tb) in relatively good yields, with their sandwich double-decker nature revealed on the basis of their mass, 1H NMR, electronic absorption, IR, and EPR spectroscopic results in addition to elemental analysis. Their electrochemistry was investigated by cyclic voltammetry (CV). In particular, magnetic studies reveal the typical slow relaxation of the terbium double-decker, indicating its typical single-ion magnet (SIM) nature with a blocking temperature of 25 K and a spin reversal energy barrier of 752 ± 8 K, representing the sole example of sandwich-type tetrapyrrole lanthanide-based SMMs reported thus far with a blocking temperature over 20 K. Theoretical calculations disclose the effect of the bulky and strong electron-donating peripheral dialkylamino groups, which create a square-antiprismatic coordination geometry and intensified coordination field strength for the central terbium ion, resulting in the excellent magnetic performance of this terbium double-decker SIM.

Unprecedented linear oligoisoindole derivatives including diisoindole, triisoindole, tetraisoindole, and hexaisoindole species, representing the new family rather than the traditional cyclic oligoisoindole ones, have been synthesized and spectroscopically characterized for the first time. Variable temperature NMR experiments in combination with DFT calculations reveal the tautomerization of the N–H protons between the outer and inner isoindole units in triisoindole, tetraisoindole, and hexaisoindole species at room temperature. The conjugated electronic structure nature of these oligoisoindole compounds has been clearly clarified on the basis of their single crystal molecular structure, electronic absorption, fluorescence, and electrochemical properties together with theoretical calculations. Moreover, the π Mayer bond order calculation suggests that these oligoisoindole compounds have two types of strong conjugated regions including the delocalized conjugated line across the whole skeleton and the localized conjugated circles at the benzene moieties, which are united together into a whole conjugated system by weak π linking bonds. In particular, the π bonds that pervade over all the linear conjugated oligoisoindole skeletons are comparable to those in the traditional cyclic oligoisoindole skeletons. This, in combination with the existence of the well-defined coordination moiety/moieties for these linear oligoisoindoles, suggests their promising application potential in diverse fields including sensors and electronic devices as their cyclic counterparts.

A new imine-linked porphyrin covalent organic framework (COF) CuP-DMNDA-COF with a large surface area was constructed from the condensation between 5,10,15,20-tetra(p-amino-phenyl)porphyrinatocopper(II) (CuTAPP) and 2,6-dimethoxynaphthalene-1,5-dicarbaldehyde (DMNDA) under solvothermal conditions. Simple treatment of CuP-DMNDA-COF with iron(III) in acetone led to the formation of the Fe-coordinated COF material CuP-DMNDA-COF/Fe, which exhibits superior adsorption performance for Rhodamine B (RhB) with easy recyclability and sustainability, indicating its good application potential for wastewater treatment.

Fabricating ultrathin two-dimensional (2D) covalent organic framework (COF) nanosheets (NSs) in large scale and high yield still remains a great challenge. This limits the exploration of the unique functionalities and wide range of application potentials of such materials. Herein, we develop a scalable general bottom-up approach to facilely synthesize ultrathin (2.1 nm) imine-based 2D COF NSs (including COF-366 NSs, COF-367 NSs, COF-367-Co NSs, TAPB-PDA COF NSs, and TAPB-BPDA COF NSs) in large scale (100 mg) and high yield (55%), via an imine-exchange synthesis strategy through adding large excess amounts of 2,4,6-trimethylbenzaldehyde into the reaction system under solvothermal conditions. Impressively, visualization of the periodic pore lattice for COF-367 NSs by a scanning tunneling microscope (STM) clearly discloses the ultrathin 2D COF nature. In particular, the ultrathin COF-367-Co NSs isolated are subject to the heterogeneous photocatalyst for CO