Silver-promoted gelation studies of an unorthodox chelating tripodal pyridine–pyrazole-based ligand: templated growth of catalytic silver nanoparticles, gas and dye adsorption
作者:Satirtha Sengupta、Arijit Goswami、Raju Mondal
DOI:10.1039/c3nj01334k
日期:——
A novel tripodal pyridineâpyrazole based tris amide ligand, namely, N1,N3,N5-tris(3-(pyridin-2-yl)-1H-pyrazol-5-yl)benzene-1,3,5-tricarboxamide was synthesized. The ligand acts as a promising low molecular weight gelator that gels silver salts in presence of water. The gels formed were found to be highly stable to heat and stress. Moreover, silver ions not only act as a gelling agent but also participate in nanoparticulate formation. The three-dimensional ligandâsilver gel matrix serves as an excellent platform for the growth of these silver nanoparticles. The gels were characterized thoroughly using IR spectroscopy, UV-visible spectroscopy, SEM, TEM and rheological studies. TEM pictures revealed the nanoparticles to be attached exclusively onto the gel fibres confirming template formation. The silver nanoparticles not only provide high strength and stability to the gel network but also show excellent catalytic properties in reducing 4-nitrophenol and Methylene Blue dye in presence of sodium borohydride. In addition to the catalytic properties, xerogels displayed gas and dye adsorption properties.
一种新型三足吡啶-吡唑基三酰胺配体,即N1,N3,N5-tris(3-(吡啶-2-基)-1H-吡唑-5-基)苯-1,3,5-三甲酰胺合成的。该配体作为一种有前途的低分子量胶凝剂,在水存在下使银盐胶凝。发现形成的凝胶对热和应力高度稳定。此外,银离子不仅充当胶凝剂,而且还参与纳米颗粒的形成。三维配体-银凝胶基质是这些银纳米颗粒生长的绝佳平台。使用红外光谱、紫外可见光谱、扫描电镜、透射电镜和流变学研究对凝胶进行了彻底的表征。 TEM 照片显示纳米粒子仅附着在凝胶纤维上,证实了模板的形成。银纳米粒子不仅为凝胶网络提供了高强度和稳定性,而且在硼氢化钠存在下还原4-硝基苯酚和亚甲基蓝染料时表现出优异的催化性能。除了催化性能外,干凝胶还具有气体和染料吸附性能。