Study On The Synthesis And Photocatalysis Of Titanium-Oxide-Clusters Based On Derivative Of Salicylate Acid

Titanium-Oxide-Clusters（TOCs）is a kind of crystal materials with great application potential,which can be used as catalysts in photocatalytic reactions.However,due to the complexity of its structure,the application is still limited.Based on this,this article will start with the diversity of the TOCs’structure,adjust the band gap of TOCs by doping transition metals and subtly changing the ligand,and try to enhance the photocatalytic performance of the TOCS,realize photocatalytic water decomposition and hydrogen production of TOCs in the presence of visible light,and catalytic degradation of organic dyes in the presence of visible light.Meanwhile,through the doping of heterometallic copper,we found that TOCs will exhibit certain nonlinear optical properties by Z-scan.the main research content of this article is divided into the following three parts:（1）We synthesized a Ti₇ cluster which is related to Anderson structure.It shows good degradation effect of organic dyes.In addition,we introduced transition metal copper ions into the system.The introduction of copper ion not only changed the structure of TOCs,but also greatly enhanced its photocatalytic water splitting to produce Hydrogen--41 times of the corresponding Anderson analogous structure.At the same time,the introduction of copper ions enhanced the intensity of the photo-responsive current of TOCs,without damaging the degradation of organic dyes.（2）The salicylic acid ligand has the characteristics of combining simple structure and rich coordination mode,which is an ideal material for studying the band gap of TOCs.In order to further study the properties of the TOCs,we selected a strong electron-withdrawing substituent Fluorine to adjust the electronic effect of the salicylic acid ligand,thereby affecting the coordination mode of the titanium atom and the salicylic acid ligand,and ultimately four types of TOCs have been obtained.According to the comparison of the photocurrent response,dye degradation and photodegradation capacity of these four TOCs,we found that the differences of the properties have shown relationships to the position of Fluorine substituents.These phenomena confirm that the substituent effect can influence not only organic synthesis,but also the formation and properties of inorganic clusters.This is helpful for the controlling of the band gap of TOCs for different properties.The experimental results show that Fluorine substitution can simultaneously enhance the photocatalytic water decomposition hydrogen production and photocatalytic degradation of dye performance of TOCs.This work provides a good example for changing the band gap of the TOCs through the adjustment of the substituent,thereby improving the catalytic performance of the TOCs.（3）In order to expand the diversity of heterometal-doped TOCs structures,we obtained two copper-doped TOCs by solvothermal method.The first one is a titanium oxide cluster with a novel butterfly structure,and the other one is a dumbbell-shaped TOCs.Through testing its photocatalytic Hydrogen production and photocurrent performance,we found that the increase of copper ions in the clusters may affect its ligand-charge transfer（LCCT）transition,resulting in the enhancement of photocatalytic performance.Through Z-scan test,we found that these Cu doped TOCs have the trend of converting saturation curve to anti saturation curve,so they can potentially be used as nonlinear optical materials.