Fabrication Of Several Self-assembled Composite Films And Electrochemical Detection,sers And Chiral Recognition Properties

Self-assembly is a technology,which spontaneously forms an ordered structure with special functions based on molecular recognition using different structures of component by weaker and reversible non-covalent bond interaction.The materials formed by supramolecular self-assembly technology have excellent physical and chemical properties and wide application value.The self-assembled films can be used in electrochemical sensing,surface-enhanced Raman scattering and corresponding selective recognition.In this paper,the preparation of nano-self-assembled composite films was studied,and we make a comprehensive study of the performance,microstructure and application of the composite films.The benzenesulfonic acid functionalized multi-walled carbon nanotubes?CNT-SO3H?/dye?including methylene blue?MB?,Rhodamine?RhB?and Safranine T?ST??composite films were prepared by LB technology.And we have researched the aggregation of dye molecules.We choosed optimum CNT-SO3H/dye Langmuir-Blodgett?LB?films for detecting metal cadmium(Cd²⁺)ions by electrochemical method.Experimental analysis showed that the synergistic effects between dye molecules and carbon nanotubes were capable of enhancing the stability and electrical activity of the composite films electrode and improving the current response signal to Cd²⁺ions detection.The difference in structure between dye molecules led in different effects on the detection of Cd²⁺ions.The benzenesulfonic acid functionalized MXene?MXene-SO3H?/dye composite films were prepared by LB technology.We have investigated the properties of the forming films,the aggregation state of dye molecules on MXene-SO3H surface and surface enhanced Raman scattering properties?SERS?.The results shows that the optimal layers of MXene-SO3H/MB films using rhodamine 6G?R6G?as probe molecule are proved to possess excellent Raman enhancement factor,uniformity and repeatability.In,addition,the assembly with different morphologies was obtained by the strong hydrogen bonds,?-?interaction between amphiphilic glutamic acid derivatives?N-?4-Aminobenzoyl?-L-glutamic acid diethyl ester?and carboxyl porphyrins?5,10,15,20-tetrakis?4-carboxyphenyl?porphyrin?and solvent effect.By adjusting the mole ratio of these two molecules and the volume ratio of mixed solvents,we obtained chiral microflower and brick-like structures,which transferred molecular chirality to the more advanced chiral structure.This work not only provides a feasible method for preparing flower-like and brick-like structures in different mixed solvents,but also provides a method for large-scale chiral transfer from molecular level to complex structures.It also provides a method for recognizing some L-and D-amino acids by measuring contact angle.