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Structure of a hyperbranched polyhydrocarbon obtained by electrochemical polymerization was analyzed by various NMR techniques and modeling. The calculated physical properties from its bulk model system well matched with experimental results.

We report the synthesis and characterization of a two-dimensional (2D) conjugated Ni(II) tetraaza[14]annulene-linked metal organic framework (NiTAA-MOF) where NiTAA is a macrocyclic MN4 (M = metal,...

Presenting a versatile method to make soft, deformable, functional metallic “putty” from liquid gallium and nonmetallic fillers., We report a versatile method to make liquid metal composites by vigorously mixing gallium (Ga) with non-metallic particles of graphene oxide (G-O), graphite, diamond, and silicon carbide that display either paste or putty-like behavior depending on the volume fraction. Unlike Ga, the putty-like mixtures can be kneaded and rolled on any surface without leaving residue. By changing temperature, these materials can be stiffened, softened, and, for the G-O–containing composite, even made porous. The gallium putty (GalP) containing reduced G-O (rG-O) has excellent electromagnetic interference shielding effectiveness. GalP with diamond filler has excellent thermal conductivity and heat transfer superior to a commercial liquid metal–based thermal paste. Composites can also be formed from eutectic alloys of Ga including Ga-In (EGaIn), Ga-Sn (EGaSn), and Ga-In-Sn (EGaInSn or Galinstan). The versatility of our approach allows a variety of fillers to be incorporated in liquid metals, potentially allowing filler-specific “fit for purpose” materials.

Correction for ‘Bottom-up synthesis of fully sp2 hybridized three-dimensional microporous graphitic frameworks as metal-free catalysts’ by S. N. Talapaneni et al., J. Mater. Chem. A, 2017, 5, 12080–12085.

Conjugated microporous polymers (CMPs) offer a unique structure integrating π- conjugated backbone into a porous network for the simultaneous transport of charges and materials. However, tuning electronic properties of CMPs so far has been limited to an approach of varying the monomers, and the precious metal catalysts are inevitably needed for the C–C coupling reaction. Here, we present a powerful strategy to synthesize CMPs and precisely tune their optical band gap and surface area through metal-free in situ cyclization reaction controlled by the acid strength of acid catalysts. Notably, the optical band gap of CMPs showed a linear relationship with the pKa of acid catalysts, which provides us with the ability to obtain the desired band gap between 2.07 and 3.35 eV, falling in the range of the visible solar spectrum. Moreover, CMPs exhibited excellent textural properties such as microporosity and high specific surface area.

We demonstrated that the ratio and position of two different metal ions, Pd and Cu, can be precisely controlled within MOFs through predesigned metal clusters. These MOF structures incorporating Pd–Cu paddle wheel units were synthesised simply by reacting Pd–Cu acetate metal clusters and tritopic organic linkers at room temperature. Pd–Cu open metal sites were found to be uniformly distributed throughout the MOFs with a ca. 1 : 1 ratio. The incorporation of Pd into the MOF structure also led to enhanced affinity towards H2 with Qst values up to 8.9 kJ mol−1.

The advent of porous polymers capable of both CO2 capture and conversion is an emerging research area to tackle ever-increasing CO2 emissions into the atmosphere and also to use CO2 as a sustainable C1 source. Porous cationic polymers, which are analogous to zeolites, with exchangeable counteranions offer ideal platform for the simultaneous capture and conversion of CO2. Here, we report on the porous cationic polymers (Ru-PCPs) with increased number of charges synthesized through condensation reaction between tris(1,10-phenanthroline-5,6-dione)Ru(II) dichloride and ortho-aromatic amines in AlCl3 at 400 °C. Ru-PCPs exhibited surface areas up to 526 m2 g−1 and CO2 uptake capacities as high as 3.76 mmol g−1, which is among the highest reported to date for porous cationic polymers. The high CO2-philicity of Ru-PCPs originating from the presence of multiple charges and nitrogen sites coupled with the nucleophilic Cl− anions rendered Ru-PCPs as highly efficient heterogeneous catalysts for the conversion of CO2 and propylene oxide to propylene carbonate through atom economy reaction. Notably, unlike previously reported porous cationic organocatalysts which require CO2 pressures of 10–30 bar, Ru-PCPs were shown to operate efficiently even under atmospheric pressure of CO2 mainly arising from the increased number of charges and counteranions.

The production of multifunctional pure organic materials that combine different sizes of pores and a large number of electron spins is highly desirable due to their potential applications as polarizers for dynamic nuclear polarization–nuclear magnetic resonance and as catalysts and magnetic separation media. Here, we report a polychlorotriphenylmethyl radical-linked covalent triazine framework (PTMR-CTF). Two different sizes of micropores were established by N2 sorption and the presence of unpaired electrons (carbon radicals) by electron spin resonance and superconducting quantum interference device–vibrating sample magnetometer analyses. Magnetization measurements demonstrate that this material exhibits spin-half paramagnetism with a spin concentration of ∼2.63 × 1023 spins/mol. We also determined the microscopic origin of the magnetic moments in PTMR-CTF by investigating its spin density and electronic structure using density functional theory calculations.

The quest for the development of new porous materials addressing both CO2 capture from various sources and its conversion into useful products is a very active research area and also critical in order to develop a more sustainable and environmentally-friendly society. Here, we present the first charged covalent triazine framework (cCTF) prepared by simply heating nitrile functionalized dicationic viologen derivatives under ionothermal reaction conditions using ZnCl2 as both solvent and trimerization catalyst. It has been demonstrated that the surface area, pore volume/size of cCTFs can be simply controlled by varying the synthesis temperature and the ZnCl2 content. Specifically, increasing the reaction temperature led to controlled increase in the mesopore content and facilitated the formation of hierarchical porosity, which is critical to ensure efficient mass transport within porous materials. The resulting cCTFs showed high specific surface areas up to 1247 m2 g-1, and high physicochemical stability. The incorporation of ionic functional moieties to porous organic polymers improved substantially their CO2 affinity (up to 133 mg g-1, at 1 bar and 273 K) and transformed them into hierarchically porous organocatalysts for CO2 conversion. More importantly, the ionic nature of cCTFs, homogeneous charge distribution together with hierarchical porosity offered a perfect platform for the catalytic conversion of CO2 into cyclic carbonates in the presence of epoxides through an atom economy reaction in high yields and exclusive product selectivity. These results clearly demonstrate the promising aspect of incorporation of charged units into the porous organic polymers for the development of highly efficient porous organocatalysts for CO2 capture and fixation. Refereed/Peer-reviewed

We report a new approach to introduce hierarchical porosity into ZIF-8 by using three-dimensional nanostructured porous ZnO as a structural template. Importantly, the textural properties of these nanostructures can be tuned simply by varying the size of the polymeric templates used for the preparation of ZnO. Moreover, the growth of ZIF-8 crystals on ZnO and the resulting hierarchical porosity enabled enhanced catalytic activity for the conversion of CO2 into cyclic carbonates through an atom economy reaction in high yields with exceptional product selectivity.

We report on the bottom-up synthesis of a fully sp2-hybridized nitrogenated three-dimensional microporous graphitic framework (3D-MGF) starting from a highly preorganized, saddle-shaped tetraphenylene derivative under ionothermal reaction conditions. The 3D-MGF showed high stability and a surface area of 928 m2 g−1 along with a narrow pore size distribution. Our approach enabled template-free inclusion of the third dimension into the graphitic frameworks while retaining π-conjugation and conductivity, which was verified by their activity as metal-free electrocatalysts for the hydrogen evolution reaction.

Summary Elemental sulfur, which is produced by a process called hydrodesulfurization mainly as a byproduct of the purification of natural gas, is one of the most abundant elements in the world. Herein, we describe solvent- and catalyst-free synthesis of ultramicroporous benzothiazole polymers (BTAPs) in the presence of elemental sulfur in quantitative yields. BTAPs were found to be highly porous and showed exceptional physiochemical stability. Moreover, in situ chemical impregnation of sulfur within the micropores increased CO 2 affinity of the sorbent while limiting diffusion of CH 4 . As low-cost, scalable solid sorbents, BTAPs showed promising CO 2 separation ability and high regenerability under vacuum swing adsorption for the simulated flue gas, natural gas, and landfill gas conditions. The fact that elemental sulfur can be directly utilized in the synthesis of BTAPs means that it can be recycled back to the natural gas sweetening process for efficient CO 2 /CH 4 separation, thus offering a high-value, scalable, large-scale application for elemental sulfur.

We present an efficient strategy for the preparation of conjugated microporous polymers incorporating pillar[5]arenes (P5-CMPs) with surface areas up to 400 m² g⁻¹ via Pd-catalyzed Sonogashira Hagihara cross-coupling reaction of triflate functionalized pillar[5]arene with 1,4-diethynylbenzene and 4,4'-diethyny1-1,1'-biphenyl linkers. In an effort to transfer intrinsic properties of pillar[5]arene, that is its ability to form strong host guest complexes with linear hydrocarbons in solution, into the solid-state, we investigated the affinity of P5-CMPs toward propane gas. Unlike previously reported porous solids, which showed isosteric heats of adsorption (Q(st)) for propane in the range of 32.9-36.9 kJ mol⁻¹ at zero coverage and increasing Q(st) with rising loading due to intermolecular interactions between propane molecules, we observed very high Q(st) values up to 53 kJ mol⁻¹ at zero coverage, which gradually decreased to similar to 35 kJ mol⁻¹ with increasing loadings. This observation indicates strong supramolecular host-guest complexation between propane and pillar[S]arene via multiple C-H/pi interactions, i.e., "macrocyclic effect" arising from the ideal size match of kinetic diameter of propane to the cavity of pillar[S]arene. This approach also allowed us to introduce thermodynamic selectivity for the separation of saturated hydrocarbons with low polarizability. High affinity of P5-CMPs for propane facilitated its efficient breakthrough separation from a simulated natural gas mixture (methane:propane, 9:1) at 298 K. Refereed/Peer-reviewed

The development of different classes of porous polymers by linking organic molecules using new chemistries still remains a great challenge. Herein, we introduce for the first time the synthesis of covalent quinazoline networks (CQNs) using an ionothermal synthesis protocol. Zinc chloride (ZnCl2 ) was used as the solvent and catalyst for the condensation of aromatic ortho-aminonitriles to produce tricycloquinazoline linkages. The resulting CQNs show a high porosity with a surface area up to 1870 m2 g-1 . Varying the temperature and the amount of catalyst enables us to control the surface area as well as the pore size distribution of the CQNs. Furthermore, their high nitrogen content and significant microporosity make them a promising CO2 adsorbent with a CO2 uptake capacity of 7.16 mmol g-1 (31.5 wt %) at 273 K and 1 bar. Because of their exceptional CO2 sorption properties, they are promising candidates as an adsorbent for the selective capture of CO2 from flue gas.

We demonstrated that the ratio and position of two different metal ions, Pd and Cu, can be precisely controlled within MOFs through predesigned metal clusters. These MOF structures incorporating Pd-Cu paddle wheel units were synthesised simply by reacting Pd-Cu acetate metal clusters and tritopic organic linkers at room temperature. Pd-Cu open metal sites were found to be uniformly distributed throughout the MOFs with a ca. 1 : 1 ratio. The incorporation of Pd into the MOF structure also led to enhanced affinity towards H

Postcombustion CO2 capture and the conversion of captured CO2 into value added chemicals are integral part of today's energy industry mainly due to their economic and environmental benefits arising from the direct utilization of CO2 as a sustainable source. Sterically confined N-heterocyclic carbenes (NHCs) have played a significant role in organocatalysis due to their air-stability, super basic nature, and strong ability to activate and convert CO2 gas. Here, we report a new class of nanoporous polymer incorporating sterically confined N-heterocyclic carbenes (NP-NHCs) that exhibit exceptional CO2 capture fixation efficiency of 97% at room temperature, which is the highest ever reported for carbene based materials measured in the solid state. The NP-NHC can also function as a highly active, selective, and recyclable heterogeneous nanoporous organocatalyst for the conversion of CO2 into cyclic carbonates at atmospheric pressure with excellent yields up to 98% along with 100% product selectivity through an atom economy reaction by using epoxides. Narrow pore size distribution of NP-NHC also allowed us to introduce a unique substrate selectivity based on size, just like enzymes, for the corresponding epoxides. This metal-free two in one approach for the CO2 gas fixation/release and conversion provides a new direction for the cost-effective, CO2 capture and conversion processes. Refereed/Peer-reviewed

Copper(I) diimine complexes have emerged as low cost replacements for ruthenium complexes as light sensitizers and electron donors, but their shorter metal-to-ligand-charge-transfer (MLCT) states lifetimes and lability of transient Cu(II) species impede their intended functions. Two carboxylated Cu(I) bis-2,9-diphenylphenanthroline (dpp) complexes [Cu(I)(dpp-O(CH2CH2O)5)(dpp-(COOH)2)](+) and [Cu(I)(dpp-O(CH2CH2O)5)(dpp-(Φ-COOH)2)](+) (Φ = tolyl) with different linker lengths were synthesized in which the MLCT-state solvent quenching pathways are effectively blocked, the lifetime of the singlet MLCT state is prolonged, and the transient Cu(II) ligands are stabilized. Aiming at understanding the mechanisms of structural influence to the interfacial charge transfer in the dye-sensitized solar cell mimics, electronic and geometric structures as well as dynamics for the MLCT state of these complexes and their hybrid with TiO2 nanoparticles were investigated using optical transient spectroscopy, X-ray transient absorption spectroscopy, time-dependent density functional theory, and quantum dynamics simulations. The combined results show that these complexes exhibit strong absorption throughout the visible spectrum due to the severely flattened ground state, and a long-lived charge-separated Cu(II) has been achieved via ultrafast electron injection (300 fs) from the (1)MLCT state into TiO2 nanoparticles. The results also indicate that the TiO2-phen distance in these systems does not have significant effect on the efficiency of the interfacial electron-transfer process. The mechanisms for electron transfer in these systems are discussed and used to develop new strategies in optimizing copper(I) diimine complexes in solar energy conversion devices.

We present a new strategy to introduce local-order into amorphous nanoporous polymers using shape-persistent organic cage compounds as molecular building blocks in the synthesis of porous cage frameworks (pCAGEs) without any metal catalyst under environmentally benign conditions. We have demonstrated that by varying the size and dimension of the organic linkers extrinsic porosity of organic cages within nanoporous polymers can be controlled, thus allowing us to tune the surface area and gas uptake properties of amorphous pCAGEs. pCAGEs (SABET = 628.7–844.3 m2 g–1) revealed significantly high CO2 uptake capacities (up to 4.21 mmol g–1 at 1 bar, 273 K) with prominent CO2/N2 IAST selectivities (up to 100). Unlike previously reported triazine-based polymers, pCAGEs showed exceptional isosteric heats of adsorption (Qst) values up to 42.9 kJ mol–1 for CO2 at high loading. We attribute the high affinity of CAGE toward CO2 to the presence of a “cage effect” arising from ultramicroporosity (intrinsic porosity) of ...

The design and synthesis of a necklace-like nitrogen-doped tubular carbon (NTC) are presented by growing microporous polyhedral ZIF-8 particles and a uniform layer of ZIF-8 on sacrificial ZnO tetrapods (ZTPs). Oxygen vacancies together with defect regions on the surface of the ZTPs result in the formation of ZIF-8 polyhedra in conjunction with a very thin shell. This necklace-like NTC structure has a high N content, very large surface area, ultrahigh microporosity, and quite high electrical conductivity. NTC-based symmetrical supercapacitor and zinc-ion capacitor (ZIC) devices are fabricated and their electrochemical performance is measured. The NTC supercapacitor shows an ultrahigh rate capability (up to 2000 mV s−1) and promising cycle life, retaining 91.5% of its initial performance after 50 000 galvanostatic charge–discharge cycles. An aqueous ZIC, constructed using the NTC, has a specific capacitance of 341.2 F g−1 at a current density of 0.1 A g−1 and an energy density of 189.6 Wh kg−1 with a 2.0-V voltage window, respectively. The outstanding performance is attributed to the NTC high N-doping content, a continuous “polyhedral 3D hollow” architecture and the highly porous microtubular arms exhibiting very high surface area.

A new strategy to form ordered hierarchical supramolecular gels that incorporate graphene oxide (GO) sheets and cationic rigid macrocyles under mild conditions via self-assembly is demonstrated. These ordered gels are stabilized by a series of non-covalent - donor-acceptor, π-π stacking, cation-π - interactions. These theoretical studies indicate that cationic macrocycles are positioned in between GO layers with a substantial binding energy.

The quest for the development of new porous materials addressing both CO

Cataloged from PDF version of article. Bodipy dyes with integral phenanthroline and terpyridine units heteroleptically assemble in the presence of zinc(II) ions to form energy transfer cassettes. These discrete complexes exhibit an approach to modularly designed efficient energy transfer and light harvesting systems through metal ion coordination.

Bright polymers: Fluorescent coordination polymers made up of versatile functionalized bodipy (boron-dipyrrin) chromophore building blocks, such as that depicted, are described. Polymerization is signaled by changes in fluorescence emission intensity and shifts in peak emission wavelengths. We designed and synthesized novel boradiazaindacene (Bodipy) derivatives that are appropriately functionalized for metal-ion-mediated supramolecular polymerization. Thus, ligands for 2-terpyridyl-, 2,6-terpyridyl-, and bipyridyl-functionalized Bodipy dyes were synthesized through Sonogashira couplings. These fluorescent building blocks are responsive to metal ions in a stoichiometry-dependent manner. Octahedral coordinating metal ions such as ZnII result in polymerization at a stoichiometry corresponding to two terpyridyl ligands to one ZnII ion. However, at increased metal ion concentrations, the dynamic equilibria are re-established in such a way that the monomeric metal complex dominates. The position of equilibria can easily be monitored by 1H NMR and fluorescence spectroscopies. As expected, although open-shell FeII ions form similar complex structures, these cations quench the fluorescence emission of all four functionalized Bodipy ligands.

A variety of advanced electrode structures have been developed lately to address the intrinsic drawbacks of lithium sulfur batteries, such as polysulfide shuttling and low electrical conductivity of elemental sulfur. Nevertheless, it is still desired to find electrode structures that address those issues through an easy synthesis while securing large sulfur contents (i.e., > 70 wt %). Here, we report an orthogonal, "one-pot" synthetic approach to prepare a sulfur-embedded polybenzoxazine (S-BOP) with a high sulfur content of 72 wt %. This sulfur-embedded polymer was achieved via thermal ring-opening polymerization of benzoxazine in the presence of elemental sulfur, and the covalent attachment of sulfur to the polymer was rationally directed through the thiol group of benzoxazine. Also, the resulting S-B OP bears a homogeneous distribution of sulfur due to in situ formation of the polymer backbone. This unique internal structure endows S-BOP with high initial Coulombic efficiency (96.6%) and robust cyclability (92.7% retention after 1000 cycles) when tested as a sulfur cathode. Refereed/Peer-reviewed

A covalent triazine framework (CTF) with embedded polymeric sulfur and a high sulfur content of 62wt% was synthesized under catalyst- and solvent-free reaction conditions from 1,4-dicyanobenzene and elemental sulfur. Our synthetic approach introduces a new way of preparing CTFs under environmentally benign conditions by the direct utilization of elemental sulfur. The homogeneous sulfur distribution is due to the insitu formation of the framework structure, and chemical sulfur impregnation within the micropores of CTF effectively suppresses the dissolution of polysulfides into the electrolyte. Furthermore, the triazine framework facilitates electron and ion transport, which leads to a high-performance lithium-sulfur battery. Refereed/Peer-reviewed

Porous cationic polymers (PCPs) with surface areas up to 755 m(2) g(-1) bearing positively charged viologen units in their backbones and different counteranions have been prepared. We have demonstrated that by simply varying counteranions both gas sorption and catalytic properties of PCPs can be tuned for metal-free capture and conversion of CO2 into value-added products such as cyclic carbonates with excellent yields. Refereed/Peer-reviewed

Functional-group-oriented polymerization strategies have contributed significantly to the initial development of porous polymers and have led to the utilization of several well-known organic transformations in the synthesis of these polymers. Because there are multiple polymerization routes that can be used to introduce the same chemical functionality, it is very important to demonstrate the effect of different polymerization routes on the gas-sorption properties of these chemically similar polymers. Herein, we have studied the rich chemistry of azobenzenes and synthesized four chemically similar nanoporous azobenzene polymers (NABs) with surface areas of up to 1021 m(2) g(-1) . The polymerization routes have a significant impact on the pore-size distributions of the NABs, which directly affects the temperature dependence of the CO2 /N2 selectivity. A pore-width maximum of 6-8 A, narrow pore-size distribution, and small particle size (20-30 nm) were very critical for high CO2 /N2 selectivity and N2 phobicity, which is associated with azo linkages and realized at warm temperatures. Our findings collectively suggest that an investigation of different polymerization routes for the same chemical functionalization is critical to understand fully the combined effect of textural properties, local environment, and chemical functionalization on the gas-sorption properties of nanoporous polymers.

A sugar and pH dual-responsive controlled release system, which is highly specific towards molecular stimuli, has been developed based on the binding between catechol and boronic acid on a platform of mesoporous silica nanoparticles (MSNs). By grafting phenylboronic acid stalks onto the silica surface, catechol-containing β-cyclodextrins can be attached to the orifices of the MSNs' nanopores through formation of boronate esters which block access to the nanopores. These esters are stable enough to prevent cargo molecules from escaping. The boronate esters disassociate in the presence of sugars, enabling the molecule-specific controlled-release feature of this hybrid system. The rate of release has been found to be tunable by varying both the structures and the concentrations of sugars, as a result of the competitive binding nature associated with the mechanism of its operation. Acidification also induces the release of cargo molecules. Further investigations show that the presence of both a low pH and sugar molecules provides cooperative effects which together control the rate of release.

The introduction of hierarchical porosity into metal-organic frameworks (MOFs) has been of considerable interest in gas separation and heterogeneous catalysis due to the efficient mass transfer kinetics through meso/macropores. Here, a facile, scalable approach is reported for the preparation of carbon nitride (CN) foams as structural templates with micrometer-sized pores and high nitrogen content of 25.6 wt% by the fast carbonization of low-cost melamine foam. The nitrogen functionalities of CN foam facilitate chemical anchoring and growth of ZIF-8 (zeolitic imidazolate frameworks) crystals, which leads to the development of hierarchical porosity. The growth of ZIF-8 crystals also renders CN foam, which is hydrophilic in nature, highly hydrophobic exhibiting 135° of water contact angle due to the enhanced surface roughness, thus creating a natural shield for the MOF crystals against water. The introduction of ZIF-8 crystals onto the CN foam enables selective absorption of oils up to 58 wt% from water/oil mixtures and also facilitates the highly efficient conversion of CO2 to chloropropene carbonate in a quantitative yield with excellent product selectivity. Importantly, this present approach could be extended to the vast number of MOF structures, including the ones suffering from water instability, for the preparation of highly functional materials for various applications.

Cataloged from PDF version of article. We report a highly selective and sensitive reversible cyanide sensor operating in the ‘turn-off-on’ mode via decomplexation of Cu(II) ions from a brightly fluorescent boradiazaindacene derivative. The sensor is reversible as the emission signal originates from the dynamic equilibration of dipicolylamine–Cu(II) and tetracyanocuprate complex ions.

A bipyridinium dication-substituted Bodipy fluorophore, with a terminal carboxylic acid function, provides two alternative stations for cucurbit[7]uril. Changing pH from basic to acidic results in shuttling of the cucurbit[7]uril from one station to another. In addition, this shuttling is accompanied by a change in the emissive properties of the Bodipy dye, which is only observed in the presence of cucurbit[7]uril. More striking, is a demonstration of autonomous shuttling of the pseudorotaxane system in an oscillating pH system.

The docking by neutral and charged guests selectively in two geometrically different binding pockets in a dynamic [2]catenane host is demonstrated in the solid state by manipulating its redox chemistry. The change in redox properties, not only alters the affinity of the host toward neutral and charged guests, but it also induces a profound change in the geometry of the host to accommodate them. X-ray crystallography, performed on the two different 1:1 complexes, demonstrates unambiguously the fact that the [2]catenane host provides a uniquely different binding pocket wherein a methyl viologen dication is stabilized by interacting with a bipyridinium radical cation, despite the presence of Coulombic repulsions.

A scalable, template-free synthetic strategy is presented for the preparation of ultramicroporous carbon nitride frameworks (CNFs) through a chemical blowing approach by using ammonium chloride as blowing agent and hexamethylene tetraamine as the C and N precursor and a subsequent potassium hydroxide chemical activation is employed to obtain CNFs with surface areas up to 1730 m(2) g(-1) along with a high nitrogen content of 13.3 wt%. CNFs showed CO2 uptake capacities up to 5.74 mmol g(-1) at 1 bar and 1.67 mmol g(-1) at 0.15 bar, 273 K along with a very high CO2/N-2 selectivity. In addition, H-2 uptake capacity of 1.9 wt% and the isosteric heats of adsorption (Q(st)) value of 9.0 kJ mol(-1) at zero coverage have been also observed. Moreover, the presence of nitrogen-doped graphene walls in CNFs also facilitated their application as supercapacitors, with capacitance values up to approximate to 114 F g(-1) at 0.5 A g(-1), along with a good cyclability and capacitance retention. This approach effectively extends unique surface properties of carbon nitrides into the micropore regime for effective capture of small gases and energy storage applications. Importantly, textural properties of CNFs can be simply tuned by judicious choice of organic precursors and the blowing agent. Refereed/Peer-reviewed

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Cataloged from PDF version of article. Versatile BODIPY dyes can be transformed into bright near-IR-emitting fluorophores by quadruple styryl substitutions. When clickable functionalities on the styryl moieties are inserted, an efficient synthesis of a light harvester is possible. In addition, clear spectral evidence is presented showing that, in dendritic light harvesters, calculations commonly based on quantum yield or emission lifetime changes of the donor are bound to yield large overestimations of energy transfer efficiency.

Remarkably versatile chemistry of Bodipy dyes allows the design and straightforward synthesis of multivalent-multitopic derivatives, which, with judicious selection of metal ion-ligand pairs based on known affinities, affords control and manipulation of photoinduced electron transfer and internal charge transfer processes as desired. We have demonstrated that metal ions acting as modulators (or inputs, in digital design parlance) can generate absorbance changes in accordance with the operation of a half-adder. In addition, an AND logic gate in the emission mode was delivered using a different binucleating arrangement of ligands. A molecular equivalent of a three-input AND logic gate was also obtained exploiting differential binding affinities of metal ions for different ligands. The results suggest that different metal ions can be used as nonannihilating inputs, selectively targeting various ligands incorporated within a single fluorophore, and with careful design, diverse photophysical processes can be selectively modulated, resulting in a range of signals, useful in molecular logic design, and offering an enticing potential for multianalyte chemosensors.

Two Bodipy derivatives with silyl-protected phenolic functionalities signal fluoride concentrations both in solution and in a poly(methyl methacrylate) matrix. The exact location of the “nascent” phenolate group is important. If it is at the meso position, photoinduced electron transfer is triggered; however, if it is in full conjugation via a styryl moiety to the Bodipy core, strong intramolecular charge transfer is triggered, resulting in a large red shift in the absorbance peak. In either case, a selective methodology for fluoride sensing is the invariable result.

1,3,5,7-Tetramethyl-Bodipy derivatives undergo Knoevenagel-type condensations with aromatic aldehydes to ultimately yield tetrastyryl-Bodipy derivatives. The resulting dyes absorb and emit strongly In the near IR. As the versatility of the Bodipy dyes are fully appreciated, these new tetrastyryl dyes are likely to be featured In a variety of functional supramolecular systems. © 2009 American Chemical Society.