Panigrahi Sudipa, Praharaj Snigdhamayee, Basu Soumen, Ghosh Sujit Kumar, Jana Subhra, Pande Surojit, Vo-Dinh Tuan, Jiang Hongjin, Pal Tarasankar
Department of Chemistry, Indian Institute of Technology, Kharagpur-721302, India.
J Phys Chem B. 2006 Jul 13;110(27):13436-44. doi: 10.1021/jp062119l.
Silver nanoparticle aggregates were synthesized in large scale using resorcinol under alkaline condition to obtain an assembly of silver clusters. Stable dispersion of the cluster in aqueous medium has been examined out of resorcinol-capped silver nanoparticle assemblies. The UV-vis spectroscopy during the particle evolution has been studied in detail. From the high-resolution TEM (HRTEM) image and XRD pattern it was confirmed that the particles are made of pure silver only. The capping action of resorcinol has been authenticated from the FTIR spectra. UV-vis spectroscopy and TEM images reveal that the temperature, effect of vibrational energy, heat shock, and time-dependent particle evolution have unique bearing on the stability and surface properties of the clusters. The concentrations of silver nitrate, resorcinol, and NaOH have important influence on the particle evolution and its size. TEM images incite us to examine the aggregates to capitulate surface-enhanced Raman scattering (SERS) to the single molecular level using crystal violet (CV) and cresyl fast violet (CFV) as molecular probes. The SERS intensity of CV increases with increasing the size of the silver aggregate.
在碱性条件下，使用间苯二酚大规模合成银纳米颗粒聚集体，以获得银簇的组装体。已从间苯二酚封端的银纳米颗粒组装体中研究了该簇在水性介质中的稳定分散情况。详细研究了颗粒演化过程中的紫外可见光谱。从高分辨率透射电子显微镜（HRTEM）图像和X射线衍射（XRD）图谱证实，这些颗粒仅由纯银制成。间苯二酚的封端作用已通过傅里叶变换红外光谱（FTIR）得到验证。紫外可见光谱和透射电子显微镜图像表明，温度、振动能量的影响、热冲击以及随时间变化的颗粒演化对簇的稳定性和表面性质具有独特的影响。硝酸银、间苯二酚和氢氧化钠的浓度对颗粒演化及其尺寸有重要影响。透射电子显微镜图像促使我们使用结晶紫（CV）和甲酚快紫（CFV）作为分子探针，研究聚集体以实现单分子水平的表面增强拉曼散射（SERS）。CV的SERS强度随着银聚集体尺寸的增加而增加。
