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An important concern for the environment is the toxicity of lead ions in aqueous solutions. In the present research, a nitrogen-enriched nanoporous polytriazine (NENP) is synthesized (SABET ∼ 700 m2 g–1), which works well as an adsorbent to remove Pb2+ from water bodies. In batch adsorption mode, 5 mg of NENP having a high nitrogen content (∼52%) is capable of reducing the concentration of Pb2+ from 1.6 ppm to <10 ppb within 10 min, at 298 K and a pH of 7. The maximum adsorption capacity of 537 mg g–1 is estimated in 10 min for 600 ppm of Pb2+ solution having a pH of 7. Meanwhile, a mixed matrix membrane designated as N-MMM was fabricated using NENP as the active adsorbent and characterized by field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and N2 sorption analysis. In a cross-flow membrane setup, N-MMM with the flux of 16.2 L m–2 h–1 can treat 5 L of an aqueous solution containing 1.6 ppm of Pb2+ and provide safe drinking water (<10 ppb by WHO) for 300 min within the permissible limit (WHO) at 2 bar transmembrane pressure and a cross-flow velocity of 1L/M. N-MMM exhibits a remarkably high removal efficiency of 99.4% and good retention ability up to 3 consecutive cycles. These findings will be beneficial for the cost-effective production of metal-free heteroatom-enriched nanoporous materials for efficient removal of Pb2+ ions from water bodies. [ABSTRACT FROM AUTHOR]

Anion-induced self-assembly is one of the growing research fields as it provides a better understanding of natural self-assemblies such as DNA, proteins, peptides, etc. Peptides are well known for their aggregation properties owing to their hydrogen bonding interactions. Herein, nanohybrids of the glutathione tripeptide and naphthalimide based compounds were fabricated, in order to explore their self-assembly behaviour. The naphthalimide based compounds were processed into organic nanoparticles using a re-precipitation method and then into nanohybrids with a tripeptide under ultrasonication conditions to get nanohybrids NH-1, NH-2 and NH-3. The morphology of prepared nanohybrids was studied by HRTEM analysis. The photophysical studies of these nanohybrids were carried out by adding various anions. NH-1 shows enhanced fluorescence intensity with bisulphate anions and the rest of the anions do not induce any change in the fluorescence intensity. Furthermore, the morphology of these nanohybrids was monitored using HRTEM and STEM. With bisulphate anions, a beautiful butterfly shaped self-assembly was observed for NH-1. The increase in intensity was a result of the aggregation induced enhanced emission mechanism. These self-assemblies have potential applications in the recognition of bisulphate with a limit of detection (LOD) of 3 nM and a limit of quantification of 10 nM respectively. [ABSTRACT FROM AUTHOR]