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The present report deals with the tailoring, preparation and characterization of novel nanomaterials sensitive to CO2 for use in detection of this gas during space habitation missions. A new nanostructured material based on mixed substituted asymmetrical A3B porphyrin: 5-(4-pyridyl)-10,15,20-tris(3,4-dimethoxyphenyl)-porphyrin (PyTDMeOPP) was synthesized and characterized by 1H-NMR, FT-IR, UV-vis, fluorescence, MS, HPLC and AFM. Introducing one pyridyl substituent in the 5-meso-position of porphyrin macrocycle confers some degree of hydrophilicity, which may cause self-assembly properties and a better response to increased acidity. The influence of pH and nature of the solvent upon H and J aggregates of the porphyrin are discussed. Porphyrin aggregation at the air–THF interface gave a triangular type morphology, randomly distributed but uniformly oriented. When deposition was made by multiple drop-casting operations, a network of triangles of uniform size was created and a porous structure was obtained, being reorganized finally in rings. When the deposition was made from CHCl3, ring structures ranging in internal diameter from 300 nm to 1 µm, but with the same width of the corona circular of approx. 200 nm were obtained. This porphyrin-based material, capable of generating ring aggregates in both THF and CHCl3, has been proven to be sensitive to CO2 detection. The dependence between the intensity of porphyrin UV-vis absorption and the concentration of CO2 has a good correlation of 98.4%.

This paper is directed towards the development of safe, and thermally stable solid polymer electrolytes. Linear phosphorus-containing (co)polyesters are described, including their synthesis, thermal analysis, conductivity, and non-flammability. Polycondensation of phenylphosphonic dichloride (PPD) with poly(ethylene glycol) (PEG 12000) with and without bisphenol A (BA) was carried out using solid-liquid phase transfer catalysis. Potassium phosphate is used as base. Yields in the range of 85.0–88.0%, and inherent viscosities in the range of 0.32–0.58 dL/g were obtained. The polymers were characterized by gel permeation chromatography, FT-IR, 1H- and 31P-NMR spectroscopy and thermal analysis. Their flammability was investigated by measuring limiting oxygen index values. The polymers are flame retardants and begin to lose weight in the 190 °C–231 °C range. Solid phosphorus- containing (co)polyesters were complexed with lithium triflate and the resulting ionic conductivity was determined. Conductivities in the range of 10−7–10−8 S cm−1 were obtained.

The present work is concerned with the manganese complexes of 5,10,15,20-tetraphenylporphyrin and of 5,10,15,20-tetra(3-hydroxyphenyl)porphyrin, which were prepared by metallation of the corresponding porphyrin ligands, and the study of their spectroscopic and photophysical behavior under strongly acidic and alkaline conditions. The second objective was to obtain and study some new hybrid materials, with special optoelectronic and surface properties, by impregnation of silica gels obtained by one step acid and by two steps acid-base catalysis with these Mn-porphyrins. The resulting nanomaterials exhibited interesting bathochromic and hyperchromic effects of their second band in the emission spectra in comparison with the Mn-porphyrins and also they have distinct orientation of the aggregates on surfaces, as shown by AFM images, making them useful for applications in medicine, formulation of sensors and for environmental-friendly catalysts for photodegradation of organic compounds.

The successful preparation of a novel dimer complex formed between 5,10,15,20-tetrakis(3,4-dimethoxyphenyl)-porphyrin Fe(III) chloride and (5,10,15,20-tetraphenylporphinato) dichlorophosphorus(V) chloride using the well-known reactivity of the P–X bond is reported. The obtained complex was characterized by UV-vis, Fourier transform infrared spectroscopy (FT-IR), fluorescence, 1H-NMR, 13C-NMR, and 31P-NMR spectroscopic techniques and also by additional Heteronuclear Single Quantum Coherence (HSQC) and Heteronuclear Multiple Bond Correlation (HMBC) experiments in order to correctly assign the NMR signals. Scanning electron microscopy (SEM) and EDX quantifications completed the characterizations. This novel porphyrin dimer complex demonstrated fluorescence sensing of H2O2 in water for low oxygen concentrations in the range of 40–90 µM proving medical relevance for early diagnosis of diseases such as Alzheimer’s, Parkinson’s, Huntington’s, and even cancer because higher concentrations of H2O2 than 50 μM are consideredcytotoxic for life. Due to its optical properties, this novel metalloporphyrin–porphyrin based complex is expected to show PDT and bactericidal activity under visible-light irradiation.