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Developing high connectivity (>8) three‐dimensional (3D) covalent organic frameworks (COFs) towards new topologies and functions remains a great challenge owing to the difficulty in getting high connectivity organic building blocks. This however represents the most important step towards promoting the diversity of COFs due to the still limited dynamic covalent bonds available for constructing COFs at this stage. Herein, highly connected phthalocyanine‐based (Pc‐based) 3D COFs MPc‐THHI‐COFs (M=H2, Ni) were afforded from the reaction between 2,3,9,10,16,17,23,24‐octacarboxyphthalocyanine M(TAPc) (M=H2, Ni) and 5,5′,5′′,5′′′,5′′′′,5′′′′′‐(triphenylene‐2,3,6,7,10,11‐hexayl)hexa(isophthalohydrazide) (THHI) with 12 connecting sites. Powder X‐ray diffraction analysis together with theoretical simulations and transmission electron microscopy reveals their crystalline nature with an unprecedented non‐interpenetrated shp topology. Experimental and theoretical investigations disclose the broadened visible light absorption range and narrow optical band gap of MPc‐THHI‐COFs. This in combination with their 3D nanochannels endows them with efficient photocatalysis performance for H2O2 generation from O2 and H2O via 2e− oxygen reduction reaction and 2e− water oxidation reaction under visible‐light irradiation (λ >400 nm). This work provides valuable result for the development of high connectivity functional COFs towards diverse application potentials. [ABSTRACT FROM AUTHOR]

Selective electrochemical CO2 reduction reaction (CO2RR) into value‐added hydrocarbon products such as C2H4 provides a sustainable approach to producing carbon chemicals, which however remains a great challenge owing to the multi‐electron transfer process during CO2 electroreduction. Herein, a tandem catalyst a‐Ni/Cu‐NP@CMK is developed by encapsulating Cu nanoparticles (Cu NPs) into hydrophobic cubic mesoporous carbon with doped atomic Ni‐N4 moieties. Electrochemical tests demonstrate the outstanding C2H4 selectivity of a‐Ni/Cu‐NP@CMK with a high Faraday efficiency (FE) of 72.3% for C2H4 at a large current density of 406.1 mA cm−2 in a flow cell under a neutral medium. Moreover, when used as the cathode catalyst in membrane electrode assembly, a‐Ni/Cu‐NP@CMK stably delivers a current density of 200 mA cm−2 with a FEC2H4 of 63% at ‐2.8 V for 30 h, providing a full‐cell energy efficiency of 28.3% for C2H4 production. Comparative studies disclose that the hydrophobic microenvironment of the Cu NPs in a‐Ni/Cu‐NP@CMK successfully suppresses the competitive hydrogen evolution reaction and improves the CO2RR selectivity. Additionally, in situ spectroscopic investigations and theoretical calculations reveal that the efficient CO2‐to‐CO conversion on the Ni‐N4 moieties feeds Cu NPs with enriched adsorbed CO (*CO), which facilitates the C─C coupling between adjacent *CO to form C2H4. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction is a viable, economical, and sustainable method to transform atmospheric CO2 into carbon-based fuels and effectively reduce climate change and the energy crisis. Constructing robust catalysts through interface engineering is significant for electrocatalytic CO2 reduction (ECR) but remains a grand challenge. Herein, SnO2/Bi2O2CO3 heterojunction on N,S-codoped-carbon (SnO2/BOC@NSC) with efficient ECR performance was firstly constructed by a facile synthetic strategy. When the SnO2/BOC@NSC was utilized in ECR, it exhibits a large formic acid (HCOOH) partial current density (JHCOOH) of 86.7 mA·cm−2 at −1.2 V versus reversible hydrogen electrode (RHE) and maximum Faradaic efficiency (FE) of HCOOH (90.75% at −1.2 V versus RHE), respectively. Notably, the FEHCOOH of SnO2/BOC@NSC is higher than 90% in the flow cell and the JHCOOH of SnO2/BOC@NSC can achieve 200 mA·cm−2 at −0.8 V versus RHE to meet the requirements of industrialization level. The comparative experimental analysis and in-situ X-ray absorption fine structure reveal that the excellent ECR performance can be ascribed to the synergistic effect of SnO2/BOC heterojunction, which enhances the activation of CO2 molecules and improves electron transfer. This work provides an efficient SnO2-based heterojunction catalyst for effective formate production and offers a novel approach for the construction of new types of metal oxide heterostructures for other catalytic applications. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Mixed phthalocyanine-porphyrin-based conjugated microporous polymers (CMPs) are still rare, limited to one sole N=N-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. [ABSTRACT FROM AUTHOR]

The Sonogashira–Hagihara coupling reaction is utilized to fabricate ethynyl-linked phthalocyanine (Pc) 2D conjugated polymers (CPs), affording the unprecedented heterometallic compound Fe0.5Co0.5Pc-CP and homometallic analogues MPc-CPs (M = Fe, Co) for comparison. It is confirmed that Fe and Co ions are well-defined/distributed with one metal ion encircled by four neighboring ions of the second metal in close proximity in the heterometallic conjugated polymer. Compared to the homometallic analogues, the bimetallic polymer Fe0.5Co0.5Pc-CP is more highly efficient for the oxygen reduction reaction (ORR), indicating that the interaction of Fe and Co ions may provide a synergistic effect on the activity. Fe0.5Co0.5Pc-CP exhibits similar ORR catalytic activity and superior stability compared to commercial Pt/C in alkaline media. Density functional theory calculations reveal that a fast 2 × 2e− synergistic catalytic reaction pathway is essential for the excellent ORR in Fe0.5Co0.5Pc-CP. [ABSTRACT FROM AUTHOR]

Abstract: A thin‐film transistor fabricated from a binuclear phthalocyanine dimer‐containing yttrium double‐decker complex [{Pc(OC4H9)8}Y{BiPc(OC4H9)12}Y{Pc(OC4H9)8}] by using the quasi–Langmuir–Shäfer technique exhibits good ambipolar organic field‐effect transistor (OFET) device performance with carrier mobilities of 2.3 and 0.8 cm2 V−1 s−1 for electrons and holes, respectively. These represent the highest mobilities achieved so far for solution‐processed small‐molecule single‐component‐based ambipolar OFET devices. The ambipolar semiconducting nature of this compound was further confirmed in an unambiguous manner by the high sensitive response of the device towards both oxidizing NO2 gas and reducing NH3 gas in the concentration range of approximately 0.5–3 ppm and 7.5–20 ppm, respectively, at room temperature. [ABSTRACT FROM AUTHOR]

A new p-azacrown[N,S,O]-styryl modified boron-phenylpyrrin compound, synchronously possessing a diethylamino receptor (C-BPP-A), has been designed and synthesized. Systematic optical studies show that C-BPP-A displays a distinct two-step fluorescence response to an increasing quantity of Cu2+, commensurate with the sequential transition from free ligand (L) to 1:1 (ML) and 2:1 (M2L) complexes: added Cu2+ ions (0-1 equiv.) are first coordinated with the p-azacrown[N,S,O] moiety of C-BPP-A, forming the 1:1 Cu2+-C-BPP-A complex and leading to significant enhancement of the fluorescence at 621 nm. Subsequently, the N atom of the diethylamino group from the Cu2+-C-BPP-A complex coordinates with the additional Cu2+ (1-2 equiv.), forming an M2L type of complex, which induces the fluorescence quenching of the 1:1 Cu2+-C-BPP-A complex at 621 nm. Meanwhile, successively increasing the added Cu2+, from 0 to 1 equiv. and from 1 to 2 equiv., also induces a gradual/fast increase, respectively, in the two-absorption-band ratio I530/ I603, accompanied by an obvious change in the solution color from blue to violet to purple. These results show C-BPP-A to be the first highly sensitive colorimetric, OFF-ON-OFF fluorescence, and absorption-ratiometric sensor for quantitative Cu2+ detection. [ABSTRACT FROM AUTHOR]

A new p-azacrown[N,S,O]-styryl modified boron-phenylpyrrin compound, synchronously possessing a diethylamino receptor (C-BPP-A), has been designed and synthesized. Systematic optical studies show that C-BPP-A displays a distinct two-step fluorescence response to an increasing quantity of Cu2+, commensurate with the sequential transition from free ligand (L) to 1:1 (ML) and 2:1 (M2L) complexes: added Cu2+ ions (0-1 equiv.) are first coordinated with the p-azacrown[N,S,O] moiety of C-BPP-A, forming the 1:1 Cu2+-C-BPP-A complex and leading to significant enhancement of the fluorescence at 621 nm. Subsequently, the N atom of the diethylamino group from the Cu2+-C-BPP-A complex coordinates with the additional Cu2+ (1-2 equiv.), forming an M2L type of complex, which induces the fluorescence quenching of the 1:1 Cu2+-C-BPP-A complex at 621 nm. Meanwhile, successively increasing the added Cu2+, from 0 to 1 equiv. and from 1 to 2 equiv., also induces a gradual/fast increase, respectively, in the two-absorption-band ratio I530/ I603, accompanied by an obvious change in the solution color from blue to violet to purple. These results show C-BPP-A to be the first highly sensitive colorimetric, OFF-ON-OFF fluorescence, and absorption-ratiometric sensor for quantitative Cu2+ detection. [ABSTRACT FROM AUTHOR]

Two mixed (phthalocyaninato)(hemiporphyrazinato) and two homoleptic bis(hemiporphyrazinato) rare earth double-decker complexes have been synthesized and structurally characterized. The EPR and NMR results clarified the protonated nature of these sandwich double-deckers. Spectroscopic and theoretical calculation results clearly reveal the predominantly aromatic nature of the mixed ring sandwich double-deckers. [ABSTRACT FROM AUTHOR]

A series of four phenanthro[4,5- fgh]quinoxaline-fused subphthalocyanine derivatives 0- 3 containing zero, one, two, and three phenanthro[4,5- fgh]quinoxaline moieties, respectively, were isolated from the mixed cyclotrimerization reaction of 2,9-di- tert-butylphenanthro[4,5- fgh]quinoxaline-5,6-dicarbonitrile with 4,5-bis(2,6-diisopropylphenoxy)phthalonitrile and characterized by a series of spectroscopic methods including MALDI-TOF mass, 1H NMR, electronic absorption, magnetic circular dichroism (MCD), and fluorescence spectroscopy. The molecular structures for the compounds 0 and 2 were clearly revealed on the basis of single-crystal X-ray diffraction analysis. Their electrochemical properties were also studied by cyclic voltammetry. In particular, theoretical calculations in combination with the electronic absorption and electrochemical analyses revealed the significant influence of the fused-phenanthro[4,5- fgh]quinoxaline units on the electronic structures. [ABSTRACT FROM AUTHOR]

The role of O2 within the synthesis of phthalocyanines (Pcs) has remained unclear in the past century. Here, we demonstrate that O2, in cooperation with the solvent n-pentanol, participates in the cyclic tetramerization of phthalonitriles over the half-sandwich complex template [Lu(Pc)(acac)] (acac=acetylacetonate) and terminates the reaction at the stage of uncyclized isoindole oligomeric derivatives rather than the phthalocyanine chromophores, resulting in the isolation of the heteroleptic (phthalocyaninato)(triisoindole-1-one) lutetium double-decker complexes [(Pc)Lu(TIO-I)] (TIO-I=3,4,7,8,11,12-sexi(2,6-diisopropylphenoxy)-15-[4,5-di(2,6-diisopropylphenoxy)-2-cyanobenzimidamido]triisoindole-1-one) and [(Pc)Lu(TIO-II)] (TIO-II=3,4,7,8,11,12-sexi(2,6-dimethylphenoxy)-15-[4,5-di(2,6-dimethylphenoxy)-2-cyanobenzimidamido]triisoindole-1-one) with the help of bulky substituents at the phthalonitrile periphery and an unsubstituted phthalocyanine ligand in the double-decker skeleton. Nevertheless, the cyclic tetramerization of the phthalonitriles was revealed to be sensitive to O2 with the reaction progression also depending on the oxygen concentration/content, leading to the O2-senstive and -dependent nature for the isolation of phthalocyanine derivatives. [ABSTRACT FROM AUTHOR]

Novel pyrene-fused unsymmetrical phthalocyanine derivatives 2,3,9,10,16,17-hexakis(2,6-dimethylphenoxy)-22,25-diaza(2,7-di- tert-butylpyrene)[4,5]phthalocyaninato zinc complex Zn[Pc(Pz-pyrene)(OC8H9)6] ( 1) and 2,3,9,10-tra(2,6-dimethylphenoxy)-15,18,22,25-traza(2,7-di- tert-butylpyrene)[4,5]phthalocyaninato zinc compound Zn[Pc(Pz-pyrene)2(OC8H9)4] ( 2) were isolated for the first time. These unsymmetrical pyrene-fused phthalocyanine derivatives have been characterized by a wide range of spectroscopic and electrochemical methods. In particular, the pyrene-fused phthalocyanine structure was unambiguously revealed on the basis of single crystal X-ray diffraction analysis of 1, representing the first structurally characterized phthalocyanine derivative fused with an aromatic moiety larger than benzene. [ABSTRACT FROM AUTHOR]

Correction for ‘Exfoliation of amorphous phthalocyanine conjugated polymers into ultrathin nanosheets for highly efficient oxygen reduction’ by Wenping Liu et al., J. Mater. Chem. A, 2019, 7, 3112–3119. [ABSTRACT FROM AUTHOR]

Unsymmetrical Pyrene ‐ Fused Phthalocyanine In the Communication on page 3168 ff., J. Jiang et al. present novel pyrene ‐ fused unsymmetrical phthalocyanine derivatives, which were isolated and characterized by a wide range of spectroscopic and electrochemical methods for the first time. In particular, the pyrene ‐ fused phthalocyanine structure was unambiguously revealed on the basis of single crystal X ‐ ray diffraction analysis of the monopyrene ‐ fused phthalocyaninato zinc derivative, representing the first structurally characterized phthalocyanine derivative fused with an aromatic moiety larger than benzene. [ABSTRACT FROM AUTHOR]

Developing high connectivity (>8) three-dimensional (3D) covalent organic frameworks (COFs) towards new topologies and functions remains a great challenge owing to the difficulty in getting high connectivity organic building blocks. This however represents the most important step towards promoting the diversity of COFs due to the still limited dynamic covalent bonds available for constructing COFs at this stage. Herein, highly connected phthalocyanine-based (Pc-based) 3D COFs MPc-THHI-COFs (M=H 2 , Ni) were afforded from the reaction between 2,3,9,10,16,17,23,24-octacarboxyphthalocyanine M(TAPc) (M=H 2 , Ni) and 5,5',5'',5''',5'''',5'''''-(triphenylene-2,3,6,7,10,11-hexayl)hexa(isophthalohydrazide) (THHI) with 12 connecting sites. Powder X-ray diffraction analysis together with theoretical simulations and transmission electron microscopy reveals their crystalline nature with an unprecedented non-interpenetrated shp topology. Experimental and theoretical investigations disclose the broadened visible light absorption range and narrow optical band gap of MPc-THHI-COFs. This in combination with their 3D nanochannels endows them with efficient photocatalysis performance for H 2 O 2 generation from O 2 and H 2 O via 2e - oxygen reduction reaction and 2e - water oxidation reaction under visible-light irradiation (λ >400 nm). This work provides valuable result for the development of high connectivity functional COFs towards diverse application potentials., (© 2024 Wiley‐VCH GmbH.)

In this paper, the 2D all-carbon graphdiyne, which possesses superior 2D strength and high mixed conductivities for both electrons and ions, is used to protect nickel cobalt oxide nanostructures with multidimensions. The in situ grown graphdiyne seamlessly wraps on nanostructures to form 3D interpenetrating networks, leading to significant improvement in the conductivity and avoidance of the structural degradation. The assembled hybrid asymmetric supercapacitor showed a high specific capacitance of 200.9 F g -1 at 1 A g -1 with an energy density of 62.8 Wh kg -1 and a power density of 747.9 W kg -1 . The device also showed a preeminent rate capability (86.4% capacitance retention, while the current density was increased from 1 to 20 A g -1 ) and an ultrastable long-term cycling performance (the capacitance retention is about 97.7% after 10 000 cycles at a high current density of 20 A g -1 ).

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 2 -to-CO conversion, showing excellent efficiency with a CO production rate as high as 10 162 μmol g -1 h -1 and a selectivity of ca. 78% in aqueous media under visible-light irradiation, far superior to corresponding bulk materials and comparable with the thus far reported state-of-the-art visible-light driven heterocatalysts.

As a vital biological mediator and a widely used industrial oxidant, the accurate detection of hydrogen peroxide (H 2 O 2 ) is of significance for both academic purpose and practical applications. Herein, we report a novel approach for the development of a high-performance electrochemical H 2 O 2 sensor constructed by iron phthalocyanine (FePc)-based diyne-linked conjugated polymeric nanosheets (NSs), FePc-CP NSs. The FePc-CP NSs were delaminated from the bulk material via a defect- and disorder-induced synthetic strategy. By the quasi-Langmuir-Shäfer method, the prepared FePc-CP NSs were self-assembled into multilayer films with controllable thickness on electrodes. Owing to the highly exposed active centers on the surfaces, the FePc-CP NS film-modified electrodes exhibited excellent H 2 O 2 determination performance with a wide linear detection range (0.1-1000 μM), a short response time (the response current approached the maximum value within 0.1 s), a low limit of detection (0.017 μM), and excellent sensitivity (97 μA cm -2 mM -1 ), which are comparable to the best results reported so far for electrochemical H 2 O 2 sensors. In addition, the fabricated electrochemical H 2 O 2 sensor also displayed satisfactory stability, reproducibility, and selectivity. Furthermore, the obtained FePc-CP NS film sensor can be applied in real-time monitoring of H 2 O 2 in commercial orange juice and beer as well as H 2 O 2 secreted from A549 live cells, revealing its application potential toward the accurate detection of H 2 O 2 in real-sample analysis.

The role of O2 within the synthesis of phthalocyanines (Pcs) has remained unclear in the past century. Here, we demonstrate that O2 , in cooperation with the solvent n-pentanol, participates in the cyclic tetramerization of phthalonitriles over the half-sandwich complex template [Lu(Pc)(acac)] (acac=acetylacetonate) and terminates the reaction at the stage of uncyclized isoindole oligomeric derivatives rather than the phthalocyanine chromophores, resulting in the isolation of the heteroleptic (phthalocyaninato)(triisoindole-1-one) lutetium double-decker complexes [(Pc)Lu(TIO-I)] (TIO-I=3,4,7,8,11,12-sexi(2,6-diisopropylphenoxy)-15-[4,5-di(2,6-diisopropylphenoxy)-2-cyanobenzimidamido]triisoindole-1-one) and [(Pc)Lu(TIO-II)] (TIO-II=3,4,7,8,11,12-sexi(2,6-dimethylphenoxy)-15-[4,5-di(2,6-dimethylphenoxy)-2-cyanobenzimidamido]triisoindole-1-one) with the help of bulky substituents at the phthalonitrile periphery and an unsubstituted phthalocyanine ligand in the double-decker skeleton. Nevertheless, the cyclic tetramerization of the phthalonitriles was revealed to be sensitive to O2 with the reaction progression also depending on the oxygen concentration/content, leading to the O2 -senstive and -dependent nature for the isolation of phthalocyanine derivatives., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)