The Study Of Surface-enhanced Raman Spectroscopy Based On Two Porous Thin Films

As a rapid and sensitive analytical technique,Surface Enhanced Raman Scattering(SERS)has attracted more and more attentions among researchers.By combining on two kinds of porous material with metal nanoparticles,several types of active substrates were developed for ultra-sensitive SERS detection.The main results and conclusions of this work are summarized as follows:1.A new kind of transparent porous alumina material was prepared with Boehmite.The BET surface-area was found to be 178m2/g with an average pore diameter of 8.67 nm and the porosity(v/v)was calculated to be 44%.Silver nanoparticles were uniformly immobilized into the channel of the porous material by photochemical method.Based on the analysis of UV,SEM,XPS and HRTEM-mapping images,the distribution of silver nanoparticles underdifferent conditions was been understand.2.A novel ultrasensitive SERS detection method was established based on the Ag-Porous ceramic layer.This detection method was so sensitive that can detect the SERS signals of crystal violet as low as 10-10M,and the reproducibility was very well.This method also showed excellent enhancement when detected the methylene blue,4-mercaptopyridine and RDX in low concentration.The SERS enhancement was also very well as the porous material combining with other metal particles.3.The titanium dioxide films with porous structure were prepared by Ti(OBu)4,polyethylene glycol as template,using the sol-gel method.The influence of raw material ratio,heat treatment temperature and the addition of polyethylene glycol were analyzed in the process.The silver nanoparticles were loaded into the pores of the titanium dioxide films by photochemical reduction.The crystallinity and purity of the silver particle were very well,and the size of the particle was changed with pore size.4.Combining the high SERS activity of silver nanoparticles and the high catalytic performance of metal-TiO2 system,we explored the activity and recycling of different Ag-TiO2 substrate.Experimental results showed that Ag-TiO2 substrate with high sensitivity,and the recycling was very good.This SERS detection method was simple and had great potential in practice for efficient SERS detection.