A Study On The Assembly Behavior Of Calixpyridine-induced Anionic Photoactive Dyes And Their Functional Applications

Supramolecular chemistry is a rapidly developing and energetic field,and its interdisciplinary nature has attracted widespread attention from scientists in various fields.An important branch in the study of supramolecular host-guest chemistry is to construct supramolecular systems with macrocyclic compounds as the host.Among them,the construction of supramolecular systems with water-soluble macrocycles as the host has made outstanding contributions in many fields.Throughout the decades of vigorous development of supramolecular chemistry,it can be found that novel macrocyclic host molecules have always played a crucial role in it.Calixpyridinium is a new type of water-soluble cationic macrocyclic host compound.In recent years,supramolecular systems based on calixpyridinium and various anionic guests through host-guest interactions have been continuously reported.However,the study of its host-guest interaction with anionic photoactive dyes has not been reported so far.I first supplemented and sorted out a previous work of the research group:the experiments on the adsorption rate and adsorption capacity of the new adsorption material of calixpyridinium-Py TS supramolecular aggregates were supplemented.The experimental data were sorted and the article was written and modified.Then,we have carried out the following work:1.The fabrication of supramolecular amphiphiles by the host-guest interactions between macrocycles and surfactants is an effective method to improve the physical and chemical properties of amphiphiles.However,as far as we know,lowering the critical micelle concentration of anionic surfactant by the complexation of macrocyclic host is scarcely studied.In this work,we systematically studied the host-guest interactions between calixpyridinium and four select anionic bola surfactants.Only congo red that has a conjugated linker could assemble into supramolecular amphiphile with calixpyridinium accompanied by a decreased critical micelle concentration.As a result,the p Ka value of congo red shifted significantly.Moreover,the calixpyridinium-congo red supramolecular amphiphilic assembly exhibited a valuable visible-light response for the complete photodegradation of congo red.It is expected that this method can be extended to construct various light-responsive supramolecular amphiphilic materials and potentially applied in many fields of materials and chemistry.2.The chemical structure of the cyanine dye IR-820 is comparable to that of the near-infrared dye indocyanine green but the absorption maximum of IR-820 experiences a significant hypsochromic shift.It has an anionic and?-conjugated structure,and can absorb visible light.In this work,a spherical calixpyridinium-IR-820 supramolecular assembled material was fabricated based on the calixpyridinium-induced IR-820 aggregation.This assembled material exhibited a well visible light responsiveness by the photodecomposition of aggregated IR-820 accompanied by an obvious color change.Such photochromic material has many potential applications.More interestingly,the photodecomposition of aggregated IR-820 was significantly promoted,although the aggregated photosensitizers usually exhibited a lower photoreactivity.This approach can be extended to construct various visible-light responsive supramolecular assembled materials in the further and potentially applied in many fields.Herein,benefitting from the p H-dependent luminescent properties of calixpyridinium and the photodegradation products of IR-820,a p H-controlled visual multicolor luminescence was achieved,which was perfectly applied in the detection of p H from 5 to 10 by naked eyes.3.We systematically studied the coordination effect and proportion of protoporphyrin sodium with Cu^II,Fe^II and Zn^II.We found that the coordination ratios of protoporphyrin sodium with these three divalent metals were all 1:1,which was consistent with the reported situation of porphyrin.Next,we further explored the host-guest interaction between calixpyridinium and protoporphyrin sodium or three metalloporphyrins.We found that the bonding ratio between calixpyridinium and protoporphyrin sodium was different from that of the three metalloporphyrins,which may be caused by the reduction of electronegativity of protoporphyrin sodium due to the introduction of metal cations,leading to the change of the bonding ratio between calixpyridinium and protoporphyrin sodium.In addition,benefitting from the p H-dependent luminescence characteristics of calixpyridinium and protoporphyrin sodium and the absorption ability of protoporphyrin sodium to visible light,we found that both calixpyridinium and Cu^II can promote the photoactivity of protoporphyrin sodium under alkaline conditions.At the same time,due to the temperature response of the supramolecular assembled material constructed by the photoreaction product of protoporphyrin sodium and calixpyridinium under alkaline conditions,a temperature-controlled fluorescence emission can be realized,and it has an excellent renaturation.Calixpyridinium-protoporphyrin sodium supramolecular material prepared under alkaline conditions can still emit bright fluorescence in solid state,and the fluorescence gradually disappears after being irradiated by incandescent lamp.This material is expected to be applied to fluorescent security ink of anti-counterfeiting strategy.