Nanometer material for SERS (Surface-Enhanced Raman Scattering) detection and preparing method of nanometer material

The invention discloses a nanometer material for SERS (Surface-Enhanced Raman Scattering) detection and a preparing method of the nanometer material. The nanometer material is composed of an inner core and an outer shell wrapping the outer side of the inner core. The inner core comprises micropore silicon dioxide particles with the particle size of 300-450 nanometers, and the outer shell is formed by gathering silver nanometer particles with the particle diameter of 5-80 nanometers. The preparing method comprises the following steps that the micropore silicon dioxide particles are prepared and a micropore silicon dioxide-silver core-shell nanometer material is prepared. The preparing method has the beneficial effects that the prepared inner core made of the nanometer material comprises the micropore silicon dioxide particles with the particle size of 300-450 nanometers, and due to the fact that a large number of micropores in the surfaces of the micropore silicon dioxide particles can load more Raman labeled molecules, the Raman labeled molecules are located in the surface local electromagnetic field generated by the silver nanometer particles on the outer layer through external lasers, SERS signals with extremely high strength are output, the nanometer material has higher SERS activity, and accordingly the SERS detection capability is greatly improved.