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Porous carbon nanohybrids are promising materials as high-performance electrodes for both sensing and energy conversion applications. This is mainly due to their high specific surface area and specific physicochemical properties. Here, new porous nanohybrid materials are developed based on exfoliated MoS2 nanopetals and either negatively charged phenylsulfonated carbon nanoparticles or positively charged sulfonamide functionalized carbon nanoparticles. MoS2 nanopetals not only act as a scaffold for carbon nanoparticles to form 3D porous hierarchical architectures but also result in well-separated electrochemical signals for different compounds. The characteristics of the new carbon nanohybrid materials are studied by dynamic light scattering, zeta potential analysis, high resolution X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy, infrared spectroscopy and electrochemistry. The new hybrid materials show superior charge transport capability and electrocatalytic activity toward selected biologically relevant compounds compared to earlier reports on porous carbon electrodes.

A family of novel unsymmetrical "peri"-substituted perylene-3,4,9,10-tetracarboxylic acid derivatives (5-10), with 1,6,7,12-tetrachloro-substituents at the bay-positions, has been synthesized. Subsequently, their redox and optical properties have been explored with the intent of unveiling opto-electronic characteristics of these newly synthesized compounds. To synthesize these new compounds, pure 1,6,7,12-tetrachloroperylene-3,4,9,10-tetracarboxylic tetra-n-butylester (4) has been employed as the precursor and the structural modifications have been carried out exclusively at the "peri" positions in an efficient manner. The two synthons prepared in this work, 1,6,7,12-tetrachloroperylene-3,4,9,10-tetracarboxylic di-n-butylester monoanhydride (5) and 1,6,7,12-tetrachloroperylene-3,4,9,10-tetracarboxylic monoimide monoanhydride (8), are extremely valuable and versatile starting materials as they possess free anhydride functionality at the "peri" position in addition to the 1,6,7,12-tetrachloro-bay-substituents. Finally, the conventional methodology for the synthesis of 1,6,7,12-tetraphenoxy-bay-functionalized perylene bisimides and perylene bisbenzimidazoles has been modified to make it faster and more convenient.

Aqueous hyaluronan (HA) solutions were hydrolyzed at pH 1.1, at various temperatures, and followed by (1) determining the increase in concentration of reducing sugar ends, and by (2) measuring the reduction in light-scattering intensity. The first method measures the chain scissions per unit time. The second method measures the change in particle size in time. From the determined chain scission rate, the evolution of the weight-averaged molecular mass of chains can be calculated. Under the assumption that the formed chain fragments immediately dissociate from the parent particle this would be equal to the evolution of the particle mass. However, the observed decay of light-scattering intensity relates to a much slower decrease of weight-averaged particle mass than predicted. Therefore, chain scission does not necessarily lead to immediate particle dissociation. Temperature-dependent measurements show that both chain scission and dissociation have similar activation energies of 97 ± 3 and 101 ± 10 kJ mol−1 respectively, showing that these two processes are coupled, and that scission is the rate-limiting process in the dissociation. The kinetic data have been interpreted using a model in which cleaved oligomers only dissociate from the parent particle if they are smaller than a critical number of disaccharide units. The critical number amounts to 26 to 33 units. From our studies accurate HA hydrolysis conditions can be extracted to obtain a desired molecular-weight distribution. Additional circular dichroism measurements show that at neutral pH, 80% of the bond angles in the HA random coil are consistent with a flat strand structure, and 20% are consistent with a double helix structure; under our applied hydrolysis conditions, HA completely possesses the flat strand structure.

The vertical ionization potentials (IP's) of a variety of free-base and zinc porphyrins and free-base and zinc phthalocyanine, including all those for which experimental ultraviolet photoelectron spectral (UPS) data are presently known, are computed using six semiempirical molecular orbital methods. Koopman's Theorem (KT), second order outer valence Green's function methods with a large number of active orbitals (OVGF), and explicit computation of the relative energies of neutral species and vertically ionized radical cations (ΔSCF IP) are used in combination with both PM3 and AM1 parameterizations, and the results are compared to experimental data. On average, both the OVGF and ΔSCF IP approximations reproduce the first vertical IP's, as determined by UPS, far more accurately than KT at minimal extra computational costs. Over the full set of available experimental data, the average error for the lowest IP with both OVGF and ΔSCF IP is only ca. 40% of that of KT (AM1 data, AM1 being generally more accurate than PM3). Inclusion of higher order terms in the OVGF treatment (third order truncation or full expression of the self-energy part) does not affect the computed IP's significantly, but inclusion of a large number of active orbitals in the OVGF technique is shown to be essential for this class of molecules. In agreement with the experimental data, zinc porphyrins and zinc phthalocyanines are computed to be better electron donors than their free-base analogues. Conformational differences of the peripheral substituents have no significant effects on the valence IP's.

The size and monolayer morphology of synthesised amphiphilic amino acid based dendrimers is studied in a Langmuir trough using Brewster Angle microscopy.

The thermotropic phase behaviour and self-assembling features of some non-ionic tetraphenylporphyrins and phthalocyanines containing oligo(ethylene oxide) alkoxy or alkyl units have been investigated. From DSC measurements and polarization microscopy it was concluded that none of the tetraphenylporphyrins was mesomorphic while the phthalocyanines displayed discotic hexagonal phases even at room temperature. The aggregation of the compounds in aqueous media was studied by means of UV–VIS and fluorescence spectroscopy and it has been found that in water the tetraphenylporphyrins form J- or head-to-tail type of aggregates while phthalocyanines form H- or face-to-face type of aggregates. The luminescence properties of the tetraphenylporphyrin and phthalocyanine aggregates are explained on the basis of the molecular exciton approximation. Steric constraints and orientational disorder in the tetraphenylporphyrin aggregates determine the luminescence yield relative to the monomeric species. The cofacial arrangement of the macrocycles in phthalocyanine aggregates results in a forbidden S 1 –S 0 transition and thus in a complete disappearance of the luminescence.

Dual fluorescent micelles with a hydrophobic probe (HMA) embedded in the micelle core and a hydrophilic probe (TRITC) attached on the micelle corona were prepared. These micelles can act as nanometre-sized thermal sensors. Within a short temperature range, the fluorescent emission of the micelles changes strongly and reversibly as a function of temperature. These micelles can be easily taken up by human HeLa cells and can potentially be used as intracellular thermometers.

A series of 1,3,5-benzenetrisamide derivatives with three hexaalkoxytriphenylene pendant groups were prepared, in which the triphenylene groups are connected to the central 1,3,5-benzenetrisamide core through a flexible spacer. The length of this spacer, as well as the size of the ortho-substituent at the triphenylene core, influences the columnar packing of these molecules. All compounds show liquid crystalline behavior with high isotropization temperatures. Different columnar hexagonal phases (Colh, Colhp, Colobl and Colr) have been identified using optical polarization microscopy, differential scanning calorimetry and X-ray diffraction. A chiral 1,3,5-benzenetrisamide derivative forms columnar stacks with a single helical sense, both in an apolar solvent and in a film, as observed by circular dichroism studies. Pulse radiolysis time-resolved microwave conductivity (PR-TRMC) studies show that the high ordering in a Colhp phase results in high charge carrier mobilities. On the other hand, the highest mobility was observed for the chiral compound, which has a Colr ordering.

A new chromogenic crown ether based on a merocyanine dye and a phenolic crown ether shows a striking selectivity for calcium or barium complexation and has a potential use in optical sensors.

Carbon-13 T1 relaxation time measurements show that the structures of 2,6-pyride crown ethers (1, n= 0–6) with ring sizes varying from 15 to 33 ring atoms and of two corresponding ‘encapsulated’ guanidinium perchlorate complexes in solution correspond to the structures in the solid state.