Fig. 1. (a) Two-dimensional rice flower configuration; (b) Three-dimensional rice flower configuration

Fig. 2. (a) Variation of the enhancement factor with the spacing d; (b) Variation of the enhancement factor with the radius of the central sphere r

Fig. 3. (a) Variation of enhancement factor with rice flower petal axis a; (b) Variation of enhancement factor with rice flower petal axis b; (c) Variation of enhancement factor with rice flower petal axis c

Fig. 4. Electric field distribution of rice flower type silver nanoparticles

Fig. 5. SEM image of the substrate. (a) 1 V; (b) 2 V; (c) 3 V

Fig. 6. XRD map

Fig. 7. SEM images of TiN-Ag composite substrates prepared by different concentration ratios of AgNO₃ to trisodium citrate

Fig. 8. SEM image of rice flower type substrate

Fig. 9. SERS patterns of different concentrations of R6G adsorbed on rice flower type TiN-Ag substrates

Fig. 10. Raman signal mapping