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This study describes the application of porphyrin-embedded porous organosilicate materials to the adsorption of ammonia gas. Organosilicate scaffolds were synthesized through a surfactant-templating process combined with a phase separation technique. The structure offers a macro-textured scaffold to facilitate flow through the sorbent material and provide enhanced access to the available surface area provided by a combination of micro- and mesopores distributed over a range of sizes. The materials were grafted post-synthesis to provide sites for covalent immobilization of porphyrins. These porphyrins were utilized for incorporation of metal sites into the organosilicate materials. The removal of ammonia was evaluated for a number of materials incorporating copper metalloporphyrins of varied structure at varied loading levels. Results have been compared to removal of ammonia by a carbon material. Copper deuteroporphyrin IX bis-ethylene glycol provided the strongest interactions with ammonia. High loading levels of this porphyrin within the sorbent structure showed increasing evidence of stacking and did not improve the performance of the material.

In the present work, the optical response of CoPcF₁₆ films upon exposure to ammonia vapor in the concentration range 50 to 1000 ppm was measured by total internal reflection ellipsometry. It was demonstrated that the sorption of NH₃ molecules causes substantial shift of the Δ(λ) spectrum which is determined by the increase in film thickness and change of its optical parameters. It was found that the CoPcF₁₆ films deposited at substrate temperature of 220 °C are characterized by larger grains and more developed surface demonstrating higher optical response than films deposited at substrate temperature of 60 °C. In order to gain an insight into the sorption mechanism at molecular level, we have studied the interaction of ammonia vapor with hexadecafluorinated cobalt phthalocyanine using infrared spectroscopy. It was shown that the detection of ammonia was found to be governed primarily by coordination to the metal center.

In the present work, we determined the electrical properties of octachlorinated metallophthalocyanines with Co(II) and Cu(II) ions as metal centers. We engaged them in heterojunctions, with lutetium bisphthalocyanine as a partner. Surprisingly, cobalt and copper complexes show opposite behaviors, the first being an $n$-type material whereas the latter is a $p$-type material, as deduced from the response of the heterojunctions towards ammonia; showing the unusual key role played by the metal center. While the LuPc${}_{\mathrm{\text{2}}}$/Cu(Cl${}_{\mathrm{\text{8}}}$Pc) complex exhibits a negative response to ammonia, the LuPc${}_{\mathrm{\text{2}}}$/Co(Cl${}_{\mathrm{\text{8}}}$Pc) complex exhibits a positive response to ammonia, with a sensitivity of 1.47% ppm${}^{\mathrm{\text{-1}}}$ at concentrations lower than 10 ppm and a limit of detection of 250 ppb. All the devices operate at room temperature and in real atmosphere.

Isoindole-diimine, which can be obtained by bubbling ammonia gas into a solution of phthalonitrile derivatives in the presence of Na${}^{+}$ ion, is a final and best precursor for phthalocyanine synthesis. In this study, isoindole-diimine and various derivatives have been prepared without bubbling ammonia gas using in situ generated ammonia that was produced from formamide and a strong alkali such as NaOH and NaNH₂. A longer reaction time, higher temperature, and larger amount of formamide were required for phthalonitrile derivatives with electron-donating groups, but this method is recommendable in that an NH₃ gas cylinder and concomitant gas regulator, which are not inexpensive, are not required. Attempts were made to interpret the IR and absorption spectra of the resultant diimines. The signals due to imino proton or N-H of diimino compounds were experimentally found to appear at around 8.2$\sim$9.5 ppm in ¹H-NMR and ca. 3500–3000 cm${}^{-1}$ in IR spectra.