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Herein, a novel type of two-component supramolecular adsorbent, 2-OA, was developed based on non-covalent interactions using tetrazolyl derivative with octadecylamine (OA) and fully characterized using a number of structural and spectral techniques. The self-assembled 2-OA gels displayed remarkable stimuli-responsiveness as well as shape-persistent and self-healing properties. In addition, it was found that the adsorbent 2-OA was able to remove dyes (10 kinds of cationic and anionic dyes) and metal ions (Cu and Fe) simultaneously from wastewater owing to synergistic electrostatic attraction, hydrogen-bonding, and hydrophobic and coordination interactions. It also exhibited excellent co-adsorption capability to dye mixtures and binary mixtures of dyes and metal ions. In particular, the dye/metal-loaded adsorbents could be obtained easily from the aqueous phase, and recycling of the adsorbents could thus be achieved. These results suggest that the supramolecular gel 2-OA not only has great potential application in wastewater treatment but also provides a strategy for the development of intriguing self-healing materials.

Supramolecular heterometallic gels with synergistic properties were prepared for the first time using ligand with Co(2+) and Ni(2+), and their macroscopic self-healing has been achieved by improving the unfavorable viscoelasticity of each monometallic gel.

A water-soluble fluorescent oil-displacing agent was prepared via copolymerization of acrylamide (AM), acrylic acid (AA) and coumarin derivatives (CO) for the first time. The rigid coumarin unit can be not only used as a fluorescent group for tracers, but also improves the heat-resistant performance of the displacement agent. The copolymer was fully characterized using FTIR, 1 H NMR, TG-DSC, UV-Vis and fluorescence measurements. The fluorescence intensity of the polymer exhibited a good linear relationship with its concentration and the linear correlation coefficient reached 0.9980, which indicated that the copolymer's concentration can be directly determined by measuring the fluorescence intensity. The pH and brine concentration of systems have no significant effect on the fluorescence intensity of the PAAC. It was also found that the viscosity retention rate of PAAC reached up to 42.3% at 100 C and PAAC exhibited excellent shear-thickening.Furthermore, up to 13.4% enhanced oil recovery was obtained using 2 g L À1 PAAC solution according to core flood tests. All results have demonstrated that the tracer copolymer PAAC with fluorescence properties exhibits great potential application for enhancing oil recovery. † Electronic supplementary information (ESI) available: The effect of synthesis conditions on copolymerization of PAAC, the excitation and emission spectra of PAAC. See