Fluorescence Enhancement Properties And Self-Cleaning Properties Of TiO₂ Nanorods

Fluorescence detection technology has great application value in the field of biomolecular and biological cell detection,but the sensitivity of fluorescence signal detection sometimes cannot meet the needs of people,and the use of high-performance fluorescence enhanced substrate is a feasible way to improve the detection sensitivity.Fluorescence enhancement basal concept is based on nano structures of basement,under the condition of the light field excitation with unique material properties,enhance the adsorption in the fluorescence enhancement fluorescein molecules excited probability near base,allowing for different fluorescein molecules fluorescence enhancement,and enhanced by fluorescein molecules fluorescence signal detection ability.Compared with the fluorescence enhanced substrate based on metal nanomaterials,inorganic non-metallic materials like silicon,silica,zinc oxide?Zn O?as a fluorescence enhanced substrate has much special advantage,such as preventing the fluorescence quenching,relatively high refractive index,controllable morphology,convenient preparation and low cost,at the same time,it also has excellent fluorescence enhancement characteristics,which has become a subject of research value.However,the fluorescence enhanced substrates studies so far still have the disadvantage of non-reuse.To address this problem,this dissertation studies the fluorescence enhancement characteristics of the florescent enhanced substrate based on TiO₂ nanorod arrays,especially the photocatalytic self-cleaning properties of TiO₂ nanorod arrays,so as to verify the reusability of the florescent enhanced substrate based on TiO₂ nanorod arrays.The main research contents of this dissertation are divided into three aspects: Firstly,preparing TiO₂ nanorod arrays.TiO₂ thin film was prepared by magnetron sputtering,and then the thin film sample was annealed to obtain TiO₂ thin film suitable for nanorod arrays seed crystal layer.TiO₂ nanorod arrays with ideal morphology were prepared on the seed crystal layer by hydrothermal method,and TiO₂ nanorods with diameters ranging from 80 nm-240 nm were obtained by changing the concentrate of titanium butoxide in the precursor solution or changing the p H of the precursor solution.Secondly,this dissertation studied the fluorescence enhancement characteristics of the TiO₂ nanorod arrays based fluorescence enhancement substrate.TiO₂ and Zn O nanorod arrays with similar diameters and densities were prepared.Using luciferin rhodamine 6G?R6G?as the fluorescence probe,the fluorescence intensity of the samples was obtained by fluorescence microscope and compared with the silicon wafer substrate without samples,which verified that TiO₂ nanorod arrays has a certain fluorescence enhancement effect on R6 G.TiO₂ nanorods with diameters of 80 nm,120 nm,160 nm,200 nm and 240 nm were prepared,and the fluorescence enhancement characteristics of TiO₂ nanorods with different diameters were compared and analyzed.The fluorescence enhancement effect of TiO₂ nanorod arrays with a diameter of 160 nm was relatively good,and the fluorescence signal strength was about 28 times that of silicon substrates.Finally,the photocatalytic self-cleaning properties of TiO₂ nanorod arrays were studied in this dissertation.To soak the tested samples of R6 G,and exposure under the xenon lamp,to adjust the appropriate ultraviolet light wavelength,exposure time,and the distance between light source and samples,measuring the intensity of fluorescence signal again under the fluorescence microscope,comparing the change of the fluorescence signal intensity before and after ultraviolet light irradiation,The degradation effects of silicon wafer,TiO₂ nanorod arrays and Zn O nanorod arrays on R6 G were compared and analyzed.To test samples of different diameter of TiO₂ nanorods,their effects on R6 G degradation were compared,including contrast degradation rate of R6 G and repeatable usability,to analysis the reasons of the differences of different samples,with a diameter of 160 nm nanorod array fluorescence signal strength of the recovery effect was best,it can achieve about 95%,and the sample showed good repeatable usability.This dissertation lays a foundation for the research and development of self-cleaning fluorescence enhanced substrates based on TiO₂ nanorod arrays.