Preparation of Gold Aerogel with High Specific Surface Area and its Application in SERS

Very recently, gold aerogels have attracted much attention as surface-enhanced Raman scattering (SERS) substrates due to their excellent plasma properties and abundant pore structures. This work shows the simple preparation of self-supported gold aerogels, which were designed as 3D SERS substrates. Ultralight porous gold aerogel (4.33[Formula: see text]mg/cm 3 ) with high surface area has been prepared by freeze casting using gold nanotubes (Au NTs) as building blocks. The SERS performance of gold aerogel-based SERS substrates has been studied by using Rhodamine 6G (R6G) as a probe molecule. Compared with the precursor Au NTs, gold aerogels have a significantly enhanced Raman signal, and the limit of detection (LOD) of R6G molecules is as low as 1 × 10[Formula: see text] M. In addition, the SERS signal intensity of the gold aerogel is also related to its density.