Preparation And Surface Enhanced Raman Performance Based On Three-Dimensional Porous Silver Micro/Nano Array Structure

Surface-enhanced Raman spectroscopy(SERS)is a powerful and widely used novel molecular vibrational spectroscopy.In recent years,reusable SERS substrates have been the goal we have been pursuing.We chose to deposit Ag nanoparticles(Ag NPs)uniformly on a 3D TiO₂ nanopore array and a 3D Si₂ porous structure as the tested SERS substrate.The main findings are as follows:1.We have prepared a new type of titanium dioxide-silver nanopore array as a strong bridge base.This semiconductor-metal three-dimensional hybrid nanostructure can achieve an 8-fold PIERS enhancement.In addition,this three-dimensional base with piers has excellent detection versatility for organic contaminants.The concentration of preservative(crystal violet)is as low as 10^-9 M.The concentrations of the agents(carbifine,phoxim and thiram)are as low as 10^-5 M.The successful incorporation of Ag nanoparticles in the TiO₂ nanopore further enhances its photocatalytic ability,and the structure is also reliable for recyclability.2.We spin-coated the graphene oxide(GO)solution onto a three-dimensional titanium dioxide-silver nanopore array.We found SERS enhancement(5.8 times)by modifying silver into a three-dimensional titanium dioxide nanopore array.Modification of GO on TiO₂ was further increased by 6.2 times Raman compared to TiO₂-Ag compared to TiO₂-Ag.The detection limit(LOD)of crystal violet(CV)was10^-8 M.Such a three-dimensional TiO₂-Ag-GO substrate is a promising SERS substrate with good sensitivity,uniformity and repeatability,and can be used for further miniaturization for analytical applications.3.In addition,our three-dimensional SiO₂-Ag micro-nano structure can detect a variety of volatile organic compounds.After silica gel-doped Ag nanoparticles,we found a 14-fold Raman enhancement with CV detection.In addition,the detection of toluene gas revealed a 7-fold SERS enhancement effect.