Department of Physics, Mar Ivanios College, Thiruvananthapuram 695015, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2012 Oct;96:1025-30. doi: 10.1016/j.saa.2012.08.010. Epub 2012 Aug 19.
The development of new synthesis methods for monodispersed nanocrystals using cheap and nontoxic chemicals, environmentally benign solvents and renewable materials remains a challenge to the scientific community. The present work reports a new green method for the synthesis of gold nanoparticles. Four different ayurvedic arishtams are used for the reduction of Au(3+) to Au nanoparticles. This method is simple, efficient, economic and nontoxic. Gold nanoparticles having different sizes in the range from 15 to 23 nm could be obtained. The nanoparticles have been characterized by UV-Visible spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and FTIR analysis. The high crystallinity of nanoparticles is evident from bright circular spots in the SAED pattern and peaks in the XRD pattern. The synthesized gold nanoparticles show good catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol by excess NaBH(4). The synthesized nanoparticles are found to exhibit size dependent catalytic property, the smaller nanoparticles showing faster activity.
使用廉价、无毒的化学品、环境友好的溶剂和可再生材料开发用于单分散纳米晶体的新合成方法仍然是科学界的一个挑战。本工作报道了一种新的绿色方法来合成金纳米粒子。四种不同的阿育吠陀药草被用于将 Au(3+)还原为 Au 纳米粒子。该方法简单、高效、经济且无毒。可以得到粒径范围为 15 至 23nm 的不同尺寸的金纳米粒子。通过紫外-可见光谱、透射电子显微镜（TEM）、X 射线衍射（XRD）和傅里叶变换红外（FTIR）分析对纳米粒子进行了表征。高结晶度的纳米粒子在选区电子衍射（SAED）图案中的亮圆形斑点和 XRD 图案中的峰中是明显的。所合成的金纳米粒子对过量的 NaBH(4)还原 4-硝基苯酚为 4-氨基酚表现出良好的催化活性。所合成的纳米粒子表现出尺寸依赖性的催化性能，较小的纳米粒子表现出更快的活性。
