Controllable Fabrication Of Ag Nanoparticle Arrays And Their SERS Performance

Recently,noble metal nanoparticle arrays have been used for surface enhanced Raman scattering(SERS)substrates owing to their superior SERS performance and become a hot research subject.In this thesis,three kinds of controllable Ag nanoparticle arrays,with efficiency,novelty and periodic structure,were designed and fabricated via some new strategies,and their SERS activities and enhancement mechanisms were studied for SERS sensors.The main achievements are as follows:Firstly,based on a combination of the monolayer polystyrene colloidal sphere template and thermal evaporation process,triangular ring silver nanoparticle arrays were prepared on the CVD grown continuous monolayer graphene film.The size of the ring is tunable.The substrate exhibits excellent SERS performance because of its unique structure and possesses the great potential in trace-detecting persistent organic pollutants in the environment.Secondly,based on the monolayer polystyrene colloidal sphere template,combined with two processes of plasma etching(used for treating the template)and thermal evaporation deposition,triangular silver nanoparticle arrays were obtained.The size and periodicity of the particle are controllable,and the optimal SERS substrate is obtained through parameter optimization.It is highly possible that this substrate receive practical application because the process is simple,green and highly repeatable.Thirdly,in order to further explore the correlation between the particle array structure and SERS enhancement,spherical silver nanoparticle arrays were synthesized via introducing simple annealing process on the basis of the second study above.The results show that great enhancement ability can also be obtained through optimization of the parameters that are different from those of the optimal triangular nanoparticle array.