LAUSR

An attractive sulfonylcalix[4]arene functionalized nanofiber membrane (sulfonylcalix-NFM) was fabricated by immobilizing the negatively charged sulfonylcalix[4]arene onto aminated polyacrylonitrile (APAN) nanofibers acting as an adsorbent and a sensor for the effective removal and naked-eye recognition of Tb3+ ions. Various factors affecting the adsorption capacities such as initial solution pH, concentration, membrane dosage, contact time and a series of foreign interfering ions were investigated in detail. The sulfonylcalix-NFM showed a maximum adsorption capacity of 123.92 mg g−1 for Tb3+, and absorbed membranes could be well regenerated without obvious compromise of removal efficiency after three repeated adsorption–desorption cycles. Moreover, it was found that the co-existing cations K+, Mg2+, and Ca2+ hardly interfered with the adsorption of Tb3+, while Cu2+, Eu3+, and La3+ could markedly reduce the removal efficiency of Tb3+. The possible adsorption mechanism of Tb3+ ions onto the sulfonylcalix-NFM was mainly attributed to the complex of the loaded sulfonylcalix[4]arene ligand with Tb3+ ions. In addition, the Tb3+-loaded sulfonylcalix-NFM exhibited good photoluminescence performance with green fluorescence under 365 nm UV radiation due to the binding of Tb3+ ions with sulfonylcalix[4]arene, which has been successfully applied for selective fluorescence recognition of Tb3+ ions with a low naked-eye detection limit of 0.5 ppm.