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The development of efficient and facile nonprecious metal catalysts for the oxygen reduction reaction (ORR) holds great significance. Among these, the single-atomic metal–nitrogen–carbon (M–N–C) catalysts are emerging candidates due to their high activity and prolonged lifespan. However, traditional preparation of M–N–C catalysts suffers from thermal aggregation and low space–time yield, limiting their application in industry. Inspired by the "chainmail protection" in carbonaceous materials, here we propose an "armor protection" strategy for the large-scale synthesis of a highly active Fe single-atom ORR catalyst (Fe-8/8-CN) by pyrolyzing a well-designed precursor Fe-ZIF-8/ZIF-8. In this precursor, the 2-methylimidazole zinc MOF (ZIF-8) loaded with iron (Fe-ZIF-8) is encased in an additional ZIF-8 armor layer (Fe-ZIF-8/ZIF-8) that effectively shields the aggregation of Fe species within the inner ZIF-8 during the pyrolysis process, ultimately yielding the Fe single-atom ORR catalyst (Fe-8/8-CN). Furthermore, the facile approaches for the construction of Fe-ZIF-8/ZIF-8 make it efficiently scale up with a high space–time yield of 18.7 kg m–3 day–1. In particular, the armor protection strategy for preparing the Fe single-atom catalyst is universally applicable to leaf-shaped ZIF-L and other ZIFs with diverse morphologies. Thanks to the presence of the outer ZIF-8 layer and the inner ZIF-8 core to dispersing Fe single-atom catalytic sites with the porous and defect-rich characteristics from the volatilization of Zn in ZIF-8, the resulting Fe-8/8-CN demonstrates superior ORR performance in alkaline electrolyte (E1/2 = 0.93 V, JL = −5.89 mA cm–2). Finally, Fe-8/8-CN, as the cathode material for flexible zinc–air batteries, exhibits a high peak power density (97 mW cm–2) and excellent durability superior to Pt/C. [ABSTRACT FROM AUTHOR]

The highly sensitive and selective detection of trace hazardous gases at room temperature is very promising for health protection and environmental safety. Herein, chemiresistive sensors for NO 2 were fabricated based on self-assembled films of the four metalloporphyrin (MPor)-based metal-organic frameworks PCN-222-M (M = Cu, Ni, Co, Fe) by the quasi-Langmuir-Shäfer method. It is found that the relative responses of the four PCN-222-M films are linearly related to the NO 2 concentration, and the PCN-222-Cu possessed an unprecedented high response to NO 2 with a sensitivity of 2209% ppm -1 in the 4-20 ppb range and a low limit of detection (LOD) of 0.93 ppb, achieving the best performance reported so far for NO 2 detection at room temperature. Meanwhile, PCN-222-Ni showed the fastest recovery among the four PCN-222-M films, which can be used for the rapid detection of NO 2 . Excellent reproducibility, stability, selectivity, and moisture resistance are shown for both PCN-222-Cu and PCN-222-Ni. Combining the experimental study and density functional theory (DFT) calculation, the essential roles of MPor units and the MPor/Zr 6 cluster hybrid material in tuning the Fermi level and the electron transfer between PCN-222-M and NO 2 were further proved. These were less considered topics in previous studies on MOFs. This work explores the application of MPor-based MOFs in gas sensing by selecting appropriate MPor units, thus providing guidance for the development of MOF-based chemiresistive sensors.

Hydrogen gas (H 2 ) as a fuel has the advantages of high energy density (122 kJ g -1 ) and zero carbon emissions. To meet the growing demand for H 2 in the future, green, efficient, and convenient production technologies must be developed. The Al-H 2 O reaction, which produces H 2 by reacting aluminum (Al) with water (H 2 O), is considered a rapid method for producing H 2 . However, Al-H 2 O creates a protective oxide layer on the surface of Al, preventing the production of H 2 . In this study, we developed a simple method for forming Al-GaInSn alloy by brushing GaInSn-Al 2 O 3 grease onto an Al plate to form an Al/GaInSn-Al 2 O 3 /Al sandwich structure. Al 2 O 3 in the sample supports GaInSn, prevents the leakage of GaInSn, and promotes its penetration into the Al lattice to form Al-GaInSn alloy. By forming a liquid phase within the alloy, GaInSn increases the accessibility of Al to the reaction. As a result, the Al-GaInSn alloy can rapidly react with pure H 2 O to produce H 2 at room temperature conditions, with yields as high as ∼93.2%. It was interesting to find that dye-polluted water (methyl orange) could be synchronically purified by the Al-H 2 O reaction at the same time.

The nonradiative carrier recombination at the perovskite/carrier selective layer (CSL) interface was accounted for the inferior power conversion efficiency (PCE) of perovskite solar cells (PSCs), especially rigid all-inorganic perovskite (CsPbI 3 and CsPbBr 3 ). In this study, targeting the poor interface, we introduce SbX 3 (X = Cl, Br, I) surface passivation at the CsPbBr 3 /carbon interface. Smoothed compressive strain, reduced defect density, and enhanced energy-level alignment were achieved simultaneously, facilitating carrier extraction at the selective interface. With the simple aqueous solution-based two-step process, the PCE of our SbI 3 passivated carbon-based CsPbBr 3 PSCs has increased from 7.81% (without passivation) to 9.69%, a ∼25% enhancement. Specifically, V oc (1.657 V) of the SbI 3 -passivated cells was much higher than that of the control ones (1.488 V), confirming the ameliorated interface. Finally, our unencapsulated SbI 3 passivated devices maintain 90% of their initial PCEs while left in the air for 30 days with a relative humidity of 60%. To conclude, we present an interfacial carrier extraction-enhanced strategy for preparing high-performance and stable CsPbBr 3 -based PSCs.

Due to the low cost and printable nature of the carbon paste, carbon-based perovskite solar cells (PSCs) are attractive for real application. However, the poor contact at the perovskite/carbon interface obviously hinders the achievable fill factor of the carbon-based PSCs. In this work, we introduce a pressure-assisted method to improve the contact at the perovskite/carbon interface. Via modulating the applied pressure, the power conversion efficiency of CsPbBr 3 PSCs (small area) can be improved from the initial 7.40% to 7.95% (pressing) and 8.34% (hot-pressing). A more remarkable feature is that the hot-pressing process boosted the performance from 5.1% (normal) to 6.9% (hot-pressing assisted) of large-scale (0.5 cm 2 ) devices, a more than 30% enhancement. Finally, the hot-pressing method introduced in this work shows great prospects for improving the efficiency of carbon-based PSCs, especially large-scale PSCs., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Developing high-efficiency and low-cost multifunctional electrocatalysts is the core of unitized regenerative fuel cells (URFC), yet it remains a great challenge. Here, by performing first-principles calculations, we report the atomic-level electrocatalytic activity mechanism of 3d, 4d, and 5d monoatomic transition metals (TM) bound to the 1T-MoS 2 monolayer for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Their structural stabilities are evaluated via the formation energy, elastic constant, and molecular dynamics simulations. Compared with the Co-N 4 -C single atom catalyst (SAC), the resulting Pd@1T-MoS 2 SAC exhibits better bifunctional catalytic activity, with OER overpotential as low as 0.43 V and an ORR overpotential of 0.40 V. The dual volcano plot demonstrates that the bifunctional OER and ORR activities of Pd@1T-MoS 2 originate from the neither strong nor weak OH* adsorption and the suitable d -band center (-1.83 eV) of the Pd active center. In conjunction with the intrinsic activity of the 1T-MoS 2 monolayer for hydrogen evolution reaction, the Pd@1T-MoS 2 SAC is a competitive and promising trifunctional electrocatalyst for sustainable energy conversion and storage systems., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

The rapid development in synthesis methodology and applications for covalent organic frameworks (COFs) has been witnessed in recent years. However, the synthesis of highly stable functional COFs still remains a great challenge. Herein two-dimensional polyimide-linked phthalocyanine COFs (denoted as CoPc-PI-COF-1 and CoPc-PI-COF-2) have been devised and prepared through the solvothermal reaction of the tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato cobalt(II) with 1,4-phenylenediamine and 4,4'-biphenyldiamine, respectively. The resultant CoPc-PI-COFs with a four-connected sql net exhibit AA stacking configurations according to powder X-ray diffraction studies, showing permanent porosity, thermal stability above 300 °C, and excellent resistance to a 12 M HCl aqueous solution for 20 days. Current-voltage curves reveal the conductivity of CoPc-PI-COF-1 and CoPc-PI-COF-2 with the value of 3.7 × 10 -3 and 1.6 × 10 -3 S m -1 , respectively. Due to the same Co(II) electroactive sites together with similar permanent porosity and CO 2 adsorption capacity for CoPc-PI-COFs, the cathodes made up of COFs and carbon black display a similar CO 2 -to-CO Faradaic efficiency of 87-97% at applied potentials between -0.60 and -0.90 V (vs RHE) in 0.5 M KHCO 3 solution. However, in comparison with the CoPc-PI-COF-2&carbon black electrode, the CoPc-PI-COF-1 counterpart provides a larger current density ( j CO ) of -21.2 mA cm -2 at -0.90 V associated with its higher conductivity. This cathode also has a high turnover number and turnover frequency, amounting to 277 000 and 2.2 s -1 at -0.70 V during 40 h of measurement. The present result clearly discloses the great potential of 2D porous crystalline solids in electrocatalysis.

Activatable triplet photosensitization refers to a photosentization process which can be turned on/off easily by external stimulus. Activatable triplet photosensitizations are normally achieved by interfering with the singlet excited state before the intersystem cross process (ISC), i.e., the formation process of triplet states of sensitizer. To achieve novel activatable triplet photosensitization, a disulfide-bridged porphyrin zinc(II) dyad (ZnPor-S-S-ZnPor) is prepared. Although fast ISC can be conducted in this dyad, an extremely low efficiency is obtained when employing this dyad as a triplet donor in triplet-triplet annihilation upconversion (TTA-UC) for sensitizing perylene. This is because of the presence of electron transfer from the triplet state of the porphyrin zinc(II) unit to the disulfide bond, which quickly quenches the triplet state of the porphyrin zinc(II) unit. This electron transfer process can be stopped by the cleavage of the disulfide bond in the presence of thiol, and TTA-UC efficiency can be enhanced significantly. Our result demonstrates for the first time that the disulfide bond can act as not only an easy cleavage linker but also a triplet electron acceptor. Furthermore, quenching the triplet states of sensitizer by triplet electron transfer provides an alternative protocol for designing activatable triplet sensitizers except controlling the singlet excited state before the ISC process.

Under compression, "'simple'" alkali metals and their alloys exhibit complex structural and electronic properties, leading to fundamental interest in their high-pressure behaviors. Here, the swarm-intelligence structure-searching method was employed to identify the high-pressure phases of binary interalkali Na 2 K, which has long been known to possess a MgZn 2 -Laves phase at ambient pressure, but the high-pressure behavior remains elusive. We uncovered four new structures over a pressure range of 10-500 GPa, although the compound was found to become unstable upon decomposition into Na and K from 37 to 273 GPa. In phases before decomposition, the electrons were gradually delocalized with an increase in pressure and there was charge transfer from K to Na, whereas in phases after recombination, the electrons were gradually localized into the interstitials of the crystals, showing the unexpected opposite trend of charge transfer from Na to K, remarkably, where K was found to exhibit an oxidation state beyond the -1 valence state. The results can improve our understanding of the interaction and evolution of s electrons under compression.

By spin-coating method, a thin layer of dodecylamine hydroiodide (DAHI) is introduced to the surface of perovskite CH 3 NH 3 PbI x Cl 3- x . This layer of DAHI successfully changes the surface of perovskite from hydrophilic to hydrophobic as revealed by the water contact angle measurement. Significantly enhanced fluorescence intensity and prolonged fluorescence lifetime are found for these modified films in comparison to those of unmodified perovskite films, suggesting that the number of structure defects is reduced dramatically. The compatibility between the perovskite and hole transfer layer (HTL) is also improved, which leads to more efficient hole collection from the perovskite layer by HTL as revealed by the fluorescence spectra, fluorescence decay dynamics, as well as the transient photocurrent measurements. Moreover, the perovskite solar cells (PSCs) fabricated from these modified perovskite films exhibit significantly improved humidity stability as well as promoted photoelectron conversion efficiency (PCE). The result of this research reveals for the first time that the layer of aliphatic amino hydroiodide is a multiple functions layer, which can not only improve the humidity stability but also promote the performance of PSCs by reducing the defect number and improve the compatibility between perovskite and HTL. Because the structure of aliphatic amines can be functionalized with myriad of other groups, this perovskite modification method should be very promising in promoting the performance of PSCs.

Developing nonprecious hydrogen evolution electrocatalysts that can work well at large current densities (e.g., at 1000 mA/cm 2 : a value that is relevant for practical, large-scale applications) is of great importance for realizing a viable water-splitting technology. Herein we present a combined theoretical and experimental study that leads to the identification of α-phase molybdenum diboride (α-MoB 2 ) comprising borophene subunits as a noble metal-free, superefficient electrocatalyst for the hydrogen evolution reaction (HER). Our theoretical finding indicates, unlike the surfaces of Pt- and MoS 2 -based catalysts, those of α-MoB 2 can maintain high catalytic activity for HER even at very high hydrogen coverage and attain a high density of efficient catalytic active sites. Experiments confirm α-MoB 2 can deliver large current densities in the order of 1000 mA/cm 2 , and also has excellent catalytic stability during HER. The theoretical and experimental results show α-MoB 2 's catalytic activity, especially at large current densities, is due to its high conductivity, large density of efficient catalytic active sites and good mass transport property.

A facile approach was developed for preparing the multilayer hybrid films of mixed (phthalocyaninato) (porphyrinato) europium(III) triple-decker compound (Pc)Eu(Pc)Eu[trans-T(COOCH 3 ) 2 PP] (1) and graphene oxide (GO) using the solution-processing QLS method. The combination of the nature of relatively high conductivity and great surface area for GO with the electroactive and semiconductive triple-decker compound in ITO electrode renders the hybrid film excellent sensing property for H 2 O 2 , due to the optimized triple-decker molecular packing in the uniform-sized nanoparticles (ca. 70 nm) formed on the GO surface. The amperometric responses are linearly proportional to the concentration of H 2 O 2 in the range of 0.05-1800 μM with a fast response time of 0.03 s μM -1 , a low detection limit of 0.017 μM, and good sensitivity of 7.4 μA mM -1 . The present work represents the best result of tetrapyrrole-based nonenzymatic electrochemical sensor for H 2 O 2 . Nevertheless, the triple-decker/GO/ITO also shows excellent stability, reproducibility, and selectivity, indicating the great potential of electroactive tetrapyrrole rare earth sandwich compounds in combination with GO in the field of nonenzymatic electrochemical sensors.

An amphiphilic mixed (phthalocyaninato) (porphyrinato) europium(III) triple-decker complex [Pc(OPh)8]Eu[Pc(OPh)8]Eu[TP(C≡CCOOH)PP] (1) with potential ambipolar semiconducting HOMO and LUMO energy levels has been designed, synthesized, and characterized. The OFET devices fabricated by quasi-Langmuir-Shäfer (QLS) technique at the air/water interface with nanoparticle morphology display hole mobility of 7.0 × 10(-7) cm(2) V(-1) s(-1) and electron mobility of 7.5 × 10(-7) cm(2) V(-1) s(-1), which reflects its ambipolar semiconducting nature. However, the performance of the devices fabricated via a "phase-transfer" method from n-hexane with one-dimensional nanoribbon morphology was significantly improved by 3-6 orders of magnitude in terms of hole and electron mobilities, 0.11 and 4 × 10(-4) cm(2) V(-1) s(-1), due to the enhanced π-π interaction in the direction perpendicular to the tetrapyrrole rings associated with the formation of a dimeric supramolecular structure building block depending on the intermolecular hydrogen bonding between the neighboring triple-decker molecules in the one-dimensional nanoribbons.

The direct growth of complex ternary metal oxides on three-dimensional conductive substrates is highly desirable for improving the electrochemical performance of lithium-ion batteries (LIBs). We herein report a facile and scalable strategy for the preparation of carbon nanofibers (CNFs) anchored with ZnxCo3-xO4 (ZCO) nanocubes, involving a hydrothermal process and thermal treatment. Moreover, the size of the ZCO nanocubes was adjusted by the quantity of urea used in the hydrothermal process. Serving as a binder-free anode material for LIBs, the ZnCo2O4/CNFs composite prepared using 1.0 mmol of urea (ZCO/CNFs-10) exhibited excellent electrochemical performance with high reversible capacity, excellent cycling stability, and good rate capability. More specifically, a high reversible capacity of ∼600 mAh g(-1) was obtained at a current density of 0.5 C following 300 charge-discharge cycles. The excellent electrochemical performance could be associated with the controllable size of the ZCO nanocubes and synergistic effects between ZCO and the CNFs.

Organic thin film transistor (OTFT) devices fabricated by the solution-based QLS technique from a mixed (phthalocyaninato)(porphyrinato) europium complex (TFPP)Eu[Pc(OPh)8]Eu[Pc(OPh)8] exhibit air-stable ambipolar performance with mobilities of 6.0 × 10(-5) cm(2) V(-1) s(-)1 for holes and 1.4 × 10(-4) cm(2) V(-1) s(-1) for electrons, respectively. In good contrast, the two-component bilayer heterojunction thin film devices constructed by directly growing (TFPP)Eu[Pc(OPh)8]Eu[Pc(OPh)8] on vacuum deposited (VCD) CuPc film using solution based QLS method were revealed to show unprecedented ambipolar performance with carrier mobilities of 0.16 cm(2) V(-1) s(-1) for holes and 0.30 cm(2) V(-1) s(-1) for electrons. In addition to the intrinsic role of p-type organic semiconductor, the VCD CuPc film on the substrate also acts as a good template that induces significant improvement over the molecular ordering of triple-decker compound in the film. In particular, it results in the change in the aggregation mode of (TFPP)Eu[Pc(OPh)8]Eu[Pc(OPh)8] from J-type in the single-layer film to H-type in the bilayer film according to the UV-vis, XRD, and AFM observations.

Three new perylenetetracarboxylic diimide (PDI) compounds substituted with hydrophobic and/or hydrophilic groups at the two imide nitrogen positions, namely N,N'-di[N-(4-aminophenyl)-3,4,5-tris(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)benzamide]-1,7-di(4-tert-butylphenoxy)perylene-3,4;9,10-tetracarboxylic diimide (1), N,N'-di[N-amido-3,4,5-tris(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)benzamide]-1,7-di(4-tert-butylphenoxy)perylene-3,4;9,10-tetracarboxylic diimide (2), and N-amido-3,4,5-tris(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)benzamide-N'-amido-3,4,5-tris(dodecyloxy)benzamide-1,7-di(4-tert-butylphenoxy)perylene-3,4;9,10-tetracarboxylate diimide (3), have been designed and prepared. The gelating abilities of them in different solvents have been investigated, and the results indicated that compounds 1 and 3 can form fluorescent gels whereas compound 2 cannot. The properties of the gels of compounds 1 and 3 have been investigated by UV-vis absorption and emission spectra. The results indicate that the gel of compound 1 is composed of H-aggregates, whereas the gel of compound 3 is composed of J-aggregates. The reversible transformation between gel and solution states induced by temperature change is observed. The structure of dried gel has been investigated by X-ray diffraction (XRD) experiments, and the morphology has been measured by atomic force microscopy (AFM). This research revealed successfully the crucial roles of amphiphilic properties and the side-chain conformations in controlling the gelating properties of PDI molecules. This information may be useful for the design of novel organogels based on perylenetetracarboxylic diimides.

A perylenetetracarboxylic diimide derivative, N-n-hexyl-N'-(2-hydroxyethyl)-1,7-di(4'-t-butyl)phenoxy-perylene-3,4:9,10-tetracarboxylic diimide (HO-PDI), was synthesized and self-assembled as a monolayer thin solid film on the modified surface of a quartz substrate by an ester bond between -OH groups of HO-PDI molecules and -COOH groups of p-phthalic acid grafted onto the hydrophilic pretreated SiO(2) surface. An analysis of the spectral change revealed the J-aggregate nature of HO-PDI molecules in the obtained thin solid film. With this thin solid film of HO-PDI as a template, CdS nanoparticles were deposited on it in situ, which were further characterized by electronic absorption, fluorescence, and energy-dispersive X-ray spectroscopy (EDS). The morphology of CdS nanoparticles is disklike, and the diameter is ca. 140 nm as determined by atomic force microscopy (AFM). Furthermore, electron transfer between the organic layer and CdS nanoparticles was deduced through fluorescence quenching and theoretical analysis.

Solution-vapor annealing of drop-cast thin films of meso-5,10,15,20-tetra-n-decylporphyrin H(2)T(C(10)H(21))(4)P deposited on SiO(2) substrate and quartz leads to the formation of well-defined self-assemblies. Their self-assembling properties in n-hexane vapor and chloroform vapor were comparatively investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) technique, and IR and UV-vis spectroscopy. Intermolecular pi-pi interaction in cooperation with the van der Waals interaction of metal free porphyrin and solvent-solute interaction leads to the formation of microleaves and microtube dendrites in n-hexane vapor and chloroform vapor, respectively. Electronic absorption spectroscopic data on the self-assembled microstructures reveal the J-aggregate nature in both the microleaves and microtube dendrites. However, the difference in the shift of the Soret and Q bands for the two kinds of aggregates relative to corresponding solution absorption bands indicates the dependence of the solvent-porphyrin molecular interaction during the annealing self-assembly process, which counterbalances the intermolecular interactions, particularly the hydrophobic interaction between side chains. IR and XRD results clearly reveal the higher molecular ordering nature of microtube dendrites than that of microleaves, further confirming the effect of the solvent on tuning the intermolecular interaction and in turn the molecular packing mode in aggregates of porphryin compounds. The present results appear to represent the first example of orderly micrometer-sized tube junctions and dendrites of porphyrin prepared through a self-assembly process, providing an effective and new method toward the synthesis of complicated nanotubular structures. In addition, micrometer-sized leaves and tube dendrites were revealed to show good semiconductor features. Highly reproducible and sensitive gas response characteristics have also been observed in these microstructures.

A series of five novel sandwich-type mixed (phthalocyaninato)(porphyrinato) europium triple-decker complexes with different numbers of hydroxyl groups at the meso-substituted phenyl groups of porphyrin ligand 1-5 have been designed, synthesized, and characterized. Their self-assembly properties, in particular the effects of the number and positions of hydroxyl groups on the morphology of self-assembled nanostructures of these triple-decker complexes, have been comparatively and systematically studied. Competition and cooperation between the intermolecular pi-pi interaction and hydrogen bonding in the direction perpendicular to the pi-pi interaction direction for different compounds were revealed to result in nanostructures with a different morphology from nanoleafs for 1, nanoribbons for 2, nanosheets for 3, and curved nanosheets for 4 and to spherical shapes for 5. The IR and X-ray diffraction (XRD) results reveal that, in the nanostructures of triple-decker 2 as well as 3-5, a dimeric supramolecular structure was formed through an intermolecular hydrogen bond between two triple-decker molecules, which as the building block self-assembles into the target nanostructures. Electronic absorption spectroscopic results on the self-assembled nanostructures reveal the H-aggregate nature in the nanoleafs and nanoribbons formed from triple-deckers 1 and 2 due to the dominant pi-pi intermolecular interaction between triple-decker molecules, but the J-aggregate nature in the curved nanosheets and spherical shapes of 4 and 5 depending on the dominant hydrogen bonding interaction in cooperation with pi-pi interaction among the triple-decker molecules. Electronic absorption and XRD investigation clearly reveal the decrease in the pi-pi interaction and increase in the hydrogen bonding interaction among triple-decker molecules in the nanostructures along with the increase of hydroxyl number in the order of 1-5. The present result appears to represent the first effort toward realization of controlling and tuning the morphology of self-assembled nanostructures of sandwich tetrapyrrole rare earth complexes through molecular design and synthesis.

A series of amphiphilic heteroleptic tris(phthalocyaninato) europium complexes with hydrophilic poly(oxyethylene) heads and hydrophobic alkoxy tails {Pc[(OC2H4)2OCH3]8}Eu{Pc[(OC2H4)2OCH3]8}Eu[Pc(OCnH2n + 1)8] (n = 6, 8, 10,12) (1-4) were designed and prepared from the reaction between homoleptic bis(phthalocyaninato) europium compound {Pc[(OC2H4)2OCH3]8}Eu{Pc[(OC2H4)2OCH3]8} and metal-free 2,3,9,10,16,17,23,24-octakis(alkoxy)phthalocyanine H2Pc(OCnH2n + 1)8 (n = 6, 8, 10,12) in the presence of Eu(acac)3.H2O (Hacac = acetylacetone) in boiling 1,2,4-trichlorobenzene (TCB). These novel sandwich triple-decker complexes have been characterized by a wide range of spectroscopic methods and have been electrochemically studied. With the help of the Langmuir-Blodgett (LB) technique, these typical amphiphilic triple-decker complexes have been fabricated into organic field effect transistors (OFET) with an unusual bottom contact configuration. The devices display good OFET performance with the carrier mobility for holes in the direction parallel to the aromatic phthalocyanine rings, which shows dependence on the length of the hydrophobic alkoxy side chains, decreasing from 0.46 for 1 to 0.014 cm2 V(-1) s(-1) for 4 along with the increase in the carbon number in the hydrophobic alkoxy side chains.

A series of four amphiphilic heteroleptic tris(phthalocyaninato) europium complexes with different lengths of hydrophobic alkoxy substituents on one outer phthalocyanine ligand [Pc(15C5)4]Eu[Pc(15C5)4]Eu[Pc(OCnH(2n+1))8] (n = 4, 6, 10,12) (1, 2, 4, and 5) was designed and prepared. Their film forming and organic field effect transistor properties have been systematically studied in comparison with analogous [Pc(15C5)4]Eu[Pc(15C5)4]Eu[Pc(OC8H17)8] (3). Experimental results showed that all these typical amphiphilic sandwich triple-decker molecules have been fabricated into highly ordered films by the Langmuir-Blodgett (LB) technique, which displays carrier mobility in the direction parallel to the aromatic phthalocyanine rings in the range of 0.0032-0.60 cm2 V(-1) s(-1) depending on the length of the hydrophobic alkoxy substituents. This is rationalized on the basis of comparative morphology analysis results of the LB films by the atomic force microscopy technique.