Properties And Application In SERS Of SnSe₂ Nanomaterials

Two-dimensional semiconductor nanomaterials have weak enhancement effects and unclear enhancement mechanisms,which limit their application in the field of surface-enhanced Raman scattering(SERS).Proper doping can effectively improve the SERS performance of two-dimensional semiconductor substrates,and can effectively break through the limitations of two-dimensional semiconductor compounds in SERS detection.It is of great significance in the fields of chemistry,biology,and materials science.In this study,we used different amounts of S dopants to change the surface morphology and energy level structure of two-dimensional SnSe₂nanosheets.This leads to the vibrational coupling between the substrate and the adsorbed molecules,which affects the SERS activity of the SnSe₂nanosheets.The SERS signal intensity of rhodamine 6G molecules on SnSe_0.93S_0.94is 1.3-1.7 times that of pure SnSe₂substrate.This not only provides a new way to effectively improve the SERS activity of semiconductor SERS substrates,but also helps to design more efficient and stable semiconductor SERS substrates and apply them to practical applications.The specific research content of the article includes:Discuss the use of chemical vapor deposition(CVD)to prepare SnSe_xS_ynanosheets,analyze the changes of nanosheets with different S doping concentrations,the peak intensities and peak positions of vibration modes E_1gand A_1gin SnSe_xS_ymaterials,and the surface structure and morphology with the regular changes of different doping concentrations.The result provides a regular explanation for the influence of quantitative S doping on the Raman results.The feasibility of SnSe_xS_ysemiconductor nanosheets as SERS substrates is studied,and the Raman signal of the molecules to be tested can be enhanced.In order to prove the excellent performance of the two-dimensional material,rhodamine 6G(R6G),adenosine(adenosine),and thiram were selected for characterization.By comparison,it is found that compared with the traditional SnSe₂nanosheets,it has an excellent SERS effect.Its detection limit is higher than that of traditional two-dimensional materials and proved the possibility of SnSe_xS_yin the field of SERS.To explore the relationship between appropriate doping concentration and SERS,SnSe_xS_ynanosheets doped with different S concentrations were used as the enhanced detection of SERS substrates.Experiments were carried out with traditional R6G molecules,It was found that with the increase of S doping,the effect of SERS signal intensity increase first and then decrease.When Sn:Se:S=1:1:1,the SERS properties is the best.The effect of temperature on the Raman peak and SERS of SnSe_0.94S_0.95nanosheets was studied.A low temperature zone(20-250?)was selected for the Raman measurments for SnSe_xS_ynanosheets.SER was tested at low temperature(20-60?),and it was found that the influence of temperature on a regular basis changed,and further explanation of the mechanism was carried out.Based on the physical properties of SnSe₂nanomaterials and its application in SERS,through a series of adjustments,the mechanism of the interaction between the substrate and the molecule to be measured caused the change of SRES activity is clarified,and the shape of SnSe_xS_ynanosheets is analyzed through the characterization of different instruments.The appearance and structure changes,and on this basis,the optimal solution of SERS is sought,which opens up new areas for the application of semiconductor materials in SERS...