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Abstract Towards future practical applications, it is necessary to develop the fluorescent sensors with only single fluorophore and single receptor for multiple-analytes detection. In the present work, a novel molecular sensor containing single receptor (the naphthol-azomethine-phenol framework) and single fluorophore (BODIPY), NAP-BODIPY, has been designed and synthesize. Single crystal X-ray diffraction analysis reveals the keto-enamine rather than the enol-imine constitution of the ortho-hydroxy naphthalene azomethine moiety in NAP-BODIPY. As a consequence, along with the conversion between acid and basic conditions in the mixed DMSO/H 2 O, the enol-keto tautomerization occurs in the ortho-hydroxy naphthalene azomethine moiety of NAP-BODIPY, resulting in a diverse change over the electronic absorption and fluorescence emission spectra. Moreover, addition of Cu2+ into NAP-BODIPY solution leads to an obvious red-shift in the maximum absorption and the naked-eye observed change from pale-orange to magenta turbid due to the metal-induced aggregation interaction. Nevertheless, adding Bi3+ into NAP-BODIPY solution induces a remarkable enhancement over the weak fluorescence emission owing to the inhibition of photo-induced electron transfer process. Subsequent addition of Cu2+ into the NAP-BODIPY-Bi3+ (1:10) system triggers a triple-signal change associated with the metal displacement. This, in combination with the fast responsive time of NAP-BODIPY to acid/base/Cu2+/Bi3+ (within several seconds), endows NAP-BODIPY an ultrafast-detecting sensor nature for multi-analytes. In particular, NAP-BODIPY can selectively stain lysosomes and therefore detect the pH change in live cells upon lysosomal acidification, revealing its great application potential for multiple-analytes. Graphical abstract The naphthol-azomethine-phenol-modified BODIPY molecular sensor consisting only single fluorophore and single receptor exhibits ultrafast-detection for multi-analytes (Acid/Base/Cu2+/Bi3+) and acts as good detector for lysosome upon pH change in live Hela cells. Image 1 Highlights • The new BODIPY single molecular sensor displays multi-sensing to Acid/Base/Cu2+/Bi3+. • This BODIPY sensor shows fast-response to multi-analytes based on different mechanisms. • This BODIPY sensor can act as a good lysosome acidification detector in live HeLa cells. [ABSTRACT FROM AUTHOR]

Mixed cyclic tetramerization of 5,6-dicyano-2-(4,5-bis(amylthio)-1,3-dithio-2-ylidene)-benzo[ d ]-1,3-dithiole and 1,2-dicyanobenzene with half-sandwich complex Eu(Pc)(acac) as template in the presence of DBU in refluxing n -pentanol led to the formation and isolation of a series of unprecedented tetrathiafulvalene(TTF)-fused heteroleptic bis(phthalocyaninato) europium double-deckers Eu(Pc)[Pc(TTF) n ] (n = 1–4) ( 1 , 2- cis , 2- trans , 3 , and 4 ). Electronic absorption spectroscopic results reveal the effect of fusing TTF onto the phthalocyanine chromophore of double-decker on the electronic structure of the target compounds. ESR together with the IR and electronic absorption spectra disclose the existence of unpaired electron in the newly prepared heteroleptic complexes. In particular, in addition to the Pc-chromophore based one-electron redox processes, one-electron, two-electron, three-electron, and four electron oxidation processes were clearly revealed by the electrochemical technique for the one-TTF, two-TTF, three-TTF, and four-TTF moiety-fused double-decker 1 , 2- cis and 2- trans , 3 , and 4 , respectively, indicating the significant influence of the TTF moieties fused to the double-decker electronic structure. In particular, theoretical calculations over 0 and 4 in combination with the electronic absorption spectroscopy reveal the significant influence of the fused-TTF units to the electronic structure. [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]

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]

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]

• Reaction mechanism of the aminopyridine compound was studied by DFT calculations. • The thermodynamic energy barriers and hydrogen transfer manners were identified. • Aminopyridine derivatives were designed and the catalytic activity was studied. • Advantageous effects of electrochemical catalytic CO 2 reduction were clarified. We report here the electrochemical reaction mechanism of CO 2 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 CO 2 molecule and therefore do not show catalytic activity for CO 2 reduction. In contrast, the compounds with p-π conjugation in meso -positions exhibit a good catalytic activity for the reduction of CO 2. [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]

The synthesis of formic acid/formate from CO 2 electrolysis is appealing for the sustainable production of fuels, which however requires highly active and selective electrocatalysts. Herein, supporting a series of phthalocyanine tin (IV) complexes on multi-walled carbon nanotubes (CNTs) generated three composite catalysts, namely SnPc@CNTs, SnPc-8 F@CNTs, and SnPc-8OCH 3 @CNTs. Electrochemical tests indicate the high activity of these three catalysts in particular SnPc-8 F@CNTs towards CO 2 -to-formate conversion with a maximal Faraday efficiency (FE) of 91.7% at − 1.2 V versus RHE and excellent stability in flow cell, comparable to thus far state-of-the-art catalysts towards CO 2 -to-formate conversion. Remarkably, when used as the cathode catalyst in membrane electrode assembly, SnPc-8 F@CNTs stably delivers a current density of 100 mA cm−2 with a FE formate of 85% at − 2.6 V for 200 h. A series of in situ spectroscopy tests and theoretical calculations demonstrate the significant effect of the electron-withdrawing F atoms on improving the catalytic activity of SnPc-8 F@CNTs. [Display omitted] • Tin phthalocyanines have been modulated by molecular engineering to enhance catalytic activity. • SnPc-8 F@CNTs stably delivers a current density of 100 mA cm−2 at a voltage of − 2.6 V for 200 h in full cell. • Electron-withdrawing F atom was revealed to improve the catalytic activity. [ABSTRACT FROM AUTHOR]

Silicon (Si) has become one of the most promising candidates as the anode for the next-generation high-energy-density lithium-ion batteries. High Si content is leading to the extraordinary asymmetric strain between the Si nanoparticles and current collector, which is regarded as the fundamental reason for the constant accumulation of solid electrolyte interphase, destruction in conductive network, and exfoliation of the active material, thus generating low Coulombic efficiency and short lifespan. In order to settle these detrimental effects by the asymmetric strain, an integrated interfacial engineering is developed, in which the as-formed 3D interpenetrating graphdiyne network on the Si nanoparticles is physically and chemically rooted on the array-like current collector. The enhanced interface interactions efficiently absorb the in-plane shear energy to resist in-plane deformation, resulting in out-plane-only volume deformation in the lithiation/delithiation reactions. Compared to the in-plane strain within the compression cell, the out-plane strain should be controllable, and the array-like architecture further provides an elastic space for reversibly accommodating the out-plane strain of electrodes. The method effectively reduces the stripping and volume variation of Si particles and provides a stable interface and robust ion/electron transport network. These advantages render Si anode extraordinary cyclability and rate performance, and the areal capacity is greatly increased to 7.5 mAh cm−2. [Display omitted] • An integrated interfacial strategy is developed for Si anode. • 3D interpenetrating graphdiyne suppresses the interfacial asymmetric strain. • The exfoliation of Si and collapse in conductive network are avoided. • It shows a general advantage in solving the issues in high-strain electrodes. [ABSTRACT FROM AUTHOR]