Self-assembly of tetra(aniline) nanowires in acidic aqueous media with ultrasonic irradiation

An environmentally friendly method is developed to explore the self-assembly of Ph/NH2-capped tetra(aniline) nanowires in acidic aqueous medium with ultrasonic irradiation.</p

Fluorescent Microporous Polyimides based on Perylene and Triazine for Highly CO₂-Selective Carbon Materials

Carbon dioxide (CO₂) capture from point sources like coal-fired power plants is a potential solution for stabilizing atmospheric CO₂ content to avoid global warming. Sorbents with high and reversible CO₂ uptake, high CO₂ selectivity, good chemical and thermal stability, and low cost are desired for the separation of CO₂ from N₂ in flue or natural gas. We report here, for the first time, on the synthesis of new microporous polyimide (PI) networks from the condensation of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) and 1,3,5-triazine-2,4,6-triamine (melamine) using a Lewis acid catalyst zinc acetate/imidazole complex. These PI network materials, prepared in the absence and presence of dimethyl sulfoxide (DMSO) as weak solvent template, exhibit strong fluorescence. Nitrogen-containing carbons can be accessed from our PI networks via a simple thermal pyrolysis route. The successful construction of new microporous PI networks and derived N-containing carbons is shown here to provide promising CO₂ sorbents with high uptake capacities (15 wt %) combined with exceptional selectivities over N₂ (240), while their fluorescent properties can be exploited for simple sensing

Highly Efficient and Reversible Iodine Capture in Hexaphenylbenzene-Based Conjugated Microporous Polymers

The effective and safe capture and storage of radioactive iodine (¹²⁹I or ¹³¹I) is of significant importance during nuclear waste storage and nuclear energy generation. Here we present detailed evidence of highly efficient and reversible iodine capture in hexaphenyl­benzene-based conjugated microporous polymers (HCMPs), synthesized via Buchwald–Hartwig (BH) cross-coupling of a hexakis­(4-bromo­phenyl)­benzene (HBB) core and aryl diamine linkers. The HCMPs present moderate surface areas up to 430 m² g^–1, with narrow pore size distribution and uniform ultramicropore sizes of less than 1 nm. Porous properties are controlled by the strut lengths and rigidities of linkers, while porosity and uptake properties can be tuned by changing the oxidation state of the HCMPs. The presence of a high number of amine functional groups combined with microporosity provides the HCMPs with extremely high iodine affinity with uptake capacities up to 336 wt %, which is to the best of our knowledge the highest reported to date. Two ways to release the adsorbed iodine were explored: either slow release into ethanol or quick release upon heating (with a high degree of control). Spectral studies indicate that the combination of microporosity, amine functionality, and abundant π-electrons ensured well-defined host–guest interactions and controlled uptake of iodine. In addition, the HCMPs could be recycled while maintaining 90% iodine uptake capacity (up to 295%). We envisage wider application of these materials in the facile uptake and removal of unwanted oxidants from the environment

Towards direct laser writing of actively tuneable three-dimensional photonic crystals

3D printing and actively switchable redox‐active oligo(aniline)‐based materials are combined to create novel tuneable 3D photonic materials. By a direct laser writing process, switchable functional structures with submicrometer features are fabricated. Reversible changes in the refractive index of the written materials are generated with negligible size changes