罗丹明6G的痕量检测需要具有较高的灵敏度，为提高SERS基底的增强因子从而提高检测灵敏度，设计了米花型SERS基底，采用有限元法对其拉曼增强效果进行仿真，模拟不同中心球半径r、米花花瓣轴a、b、c以及中心球与花瓣间距d条件下电场强度的变化，得出最佳结构参数，并计算其SERS增强因子。随后利用电化学沉积法制备该基底，并探究电压值以及柠檬酸三钠和AgNO₃的浓度配比对基底结构和性能的影响，从而制备出与理想物理模型形态最接近的米花型银/氮化钛薄膜基底。然后用其对罗丹明6G（R6G）进行痕量检测，探究该基底的拉曼增强效果以及稳定性。实验结果表明，当沉积电压为2V，柠檬酸三钠与AgNO₃浓度配比为1∶1 （2 mmol/L∶2 mmol/L）时，得到的米花型TiN-Ag复合SERS基底与理想化模型仿真形态最接近。经过计算得到该基底的增强因子可达10¹⁵，对罗丹明6G的检测限可达10⁻¹³ mol/L。实验结果证明设计的基底灵敏度高、稳定性强，可对食品非法添加剂的痕量检测提供技术支撑。

Rhodamine 6G (R6G), also known as Rose Red 6G, is a fluorescent dye with water solubility and is often used in optics, laser optics, dyes and other fields. It is very toxic to humans, and there is a risk of cancer from long-term exposure or use of rhodamine, so it is included in illegal additives. However, due to its low price and good coloring properties, it is often used by unscrupulous businessmen in textiles, medicine, food, etc. The current methods for detecting rhodamine are mainly high performance liquid chromatography and liquid chromatography-tandem mass spectrometry. However, the operation process is tedious and the cost is high. Therefore, it is necessary to design a new method for the rapid detection of rhodamine 6G. The performance of the substrate and the minimum detection limit of rhodamine 6G were investigated. The finite element method was used to simulate the milky substrate, and a milky silver/titanium nitride composite SERS substrate was designed and Raman detected for rhodamine 6G using electrochemical deposition method. In order to obtain the SERS enhancement effect of silver nanosubstrates with different morphological rice flower type structures and thus optimize the SERS substrate design, the electric field intensity simulation experiments were performed by the finite element method to simulate the changes of field intensity under different central sphere radius r, rice flower petal axes a, b, c, and central sphere and petal spacing d. The SERS enhancement factor was calculated. Subsequently, the substrates were prepared by electrochemical deposition and the effects of voltage value and the concentration ratios of trisodium citrate and AgNO₃ on the substrate structure and properties were investigated, so as to prepare the rice flower type silver/titanium nitride thin film substrate with the closest morphology to the idealized physical model. It was then used for trace detection of rhodamine 6G (R6G) to investigate the Raman enhancement effect of this substrate as well as its stability. The experimental results show that the obtained rice flower type TiN-Ag composite SERS substrate is closest to the idealized model simulation morphology when the deposition voltage is 2 V and the concentration ratio of trisodium citrate to AgNO₃ is 1∶1. The optimal enhancement factor of this substrate was calculated to be 10¹⁵, and the detection limit of rhodamine 6G was up to 10^-13 mol/L. Based on the finite element method simulation, the field strength of the rice flower structure substrate was compared under the conditions of different radius of the central sphere, rice flower petal axis and spacing between the central sphere and petal, and the best enhancement factor of the rice flower silver/titanium nitride thin film substrate was obtained as 10¹⁵. The rice flower TiN-Ag composite SERS substrate was obtained with the closest morphology to the rationalization model simulation and the lowest detection concentration of rhodamine 6G of 10^-13 mol/L by comparative experiments when the deposition voltage was 2 V and the concentration ratio of AgNO₃ was 1∶1.