Optical and biomedical applications of bismuth-based nanostructures could be limited due to the particle oxidation in aqueous media. To overcome this limitation, a two-step process including Nd:YAG pulsed laser ablation of bismuth and chemical reaction for shell formation have been developed to fabricate Bi/Au nanoparticles. The nanoparticles have been extensively characterized by various method including transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, optical extinction and MNPBEM simulation package using boundary element method. The prepared bismuth nanoparticles by laser ablation in toluene demonstrate a narrow size distribution with mean size of 40 nm and gold shell were synthesized on Bi core with 7 nm thickness. In optical transmission, the wavelength of maximum absorption peak due to surface plasmon resonance was at 562 nm for gold thickness between 5 and 7 nm. MNPBEM simulation results predict the trends of the experimental observation including the spherical shape and shell thickness. Oxidation resistance of nanoparticles was studied via optical extinction spectroscopy. Oxidation resistance is one of the important factors in efficiency of nanoparticles in aqueous solution as CT contrast agents Finally, Bi/Au composite nanoparticles demonstrated higher X-ray attenuation in comparison with commercial iodine molecule.

铋基纳米结构的光学和生物医学应用可能会由于水介质中的颗粒氧化而受到限制。为了克服该限制，已经开发了包括Nd：YAG脉冲铋的激光烧蚀和用于壳形成的化学反应的两步工艺来制造Bi / Au纳米颗粒。纳米粒子已通过多种方法进行了广泛表征，包括透射电子显微镜，扫描电子显微镜，能量色散X射线光谱，X射线衍射，消光和使用边界元法的MNPBEM模拟包。通过在甲苯中激光烧蚀制备的铋纳米粒子显示出窄的粒径分布，平均粒径为40 nm，并且在7 nm厚度的Bi核芯上合成了金壳。在光传输中 对于5至7 nm的金厚度，由于表面等离振子共振而产生的最大吸收峰的波长为562 nm。MNPBEM仿真结果预测了实验观察的趋势，包括球形和壳厚度。通过消光光谱研究了纳米颗粒的抗氧化性。抗氧化性是影响纳米粒子在水溶液中作为CT造影剂的效率的重要因素之一。最后，与商业化的碘分子相比，Bi / Au复合纳米粒子表现出更高的X射线衰减。通过消光光谱研究了纳米颗粒的抗氧化性。抗氧化性是影响纳米粒子在水溶液中作为CT造影剂的效率的重要因素之一。最后，与商业化的碘分子相比，Bi / Au复合纳米粒子表现出更高的X射线衰减。通过消光光谱研究了纳米颗粒的抗氧化性。抗氧化性是影响纳米粒子在水溶液中作为CT造影剂的效率的重要因素之一。最后，与商业化的碘分子相比，Bi / Au复合纳米粒子表现出更高的X射线衰减。