Figure 2From: Combination of inverted pyramidal nanovoid with silver nanoparticles to obtain further enhancement and its detection for ricin SEM images of prepared samples. a and b are SEM images of the inverted pyramidal nanovoid substrate. The pithead boundary length of the nanovoid is about 1.41 μm, its depth 1 μm, and its period 2 μm. c and d are SEM images of the prepared silver nanoparticles by solvothermal method. e and f are SEM images of the combined substrate.Back to article page