Engineered Artificial Nanochannels for Nitrite Ion Harmless Conversion

Inspired by the delicate functions of living organisms to transport or transform nitrite ions (NO2-), a bioinspired smart nanochannel that can realize harmless conversion of NO2- into N-2 is developed by immobilizing a NO2--responsive functional molecule, p-phenylenediamine, onto a single conical polyethylene terephthalate nanochannel. Subsequently, the aromatic primary amine groups could be triggered to transform into a phenyldiazonium molecule based on the acid-activated NO2--binding process. The nanochannel exhibits specific selectivity and highly ultratrace recognition of NO2-. Fascinatingly, the transformed phenyldiazonium molecules could be triggered to generate phenol groups and release N-2 by ultraviolet light activation, achieving NO2- harmless conversion. This system could provide inspiration to construct artificial nanofluidic devices for ion-sensing and nitrogen cycle fields.