Study On The Amine-acid Two-Component Gelator And Dye Selective Adsorption

The two-component gel system has been extensively studied,because the molecular structure of each component in the two-component gel system can be modified to achieve regulating gel properties.Two-component gels formed by amineacid interaction are common.In this work,two-component gelator isomers based on the different amine/acid interactions were investigated,which were N-(6-aminohexyl)-2,4-(3,4-dichlorophenylene methylene)-d-glucosamide with stearic acid(compound C6-A18)and N-(6-carboxyl hexyl)-2,4-(3,4-dichlorophenylene methylene)-d-glucosamide with stearamine(compound D6-B18).And explored the properties of the twocomponent hydrogel induced by them and the selective adsorption of xerogel for anionic and cationic dyes.Scanning electron microscopy and atomic force microscopy images of the xerogel obtained from the two hydrogels revealed different assembly morphologies.While lefthanded helical fibers were observed for the C6-A18 xerogel,D6-B18 xerogel underwent self-assembly to afford non-helical fibers.Circular dichroism demonstrated the above phenomenon.Fourier transform infrared spectroscopy,NMR spectrum and fluorescence demonstrated that the main driving forces of self-assembly are hydrogen bonds,π-π interactions and van der Waals forces.X-ray diffraction measurements demonstrated that the assembly of two-component hydrogel was layered.Based on the experiments and density functional theory calculations,a possible self-assembly pattern was proposed.The different self-assembly patterns of gelators resulted in opposite electric charges on the xerogel surfaces,in line with Zeta potential measurements.Based on these opposite charges resulting from their different self-assemblies,both xerogels demonstrated efficient dye adsorption abilities with different selectivities.Interestingly,the adsorption performance was not influenced by the salt in the dye solution,however it was influenced by p H deeply.Furthermore,the xerogels still showed high dye adsorption efficiency after four cycles.These results provide a twocomponent hydrogel method for the purification of dye-polluted water systems,while also paving the way for future design of functionalized supramolecular self-assembly systems.