表面覆盖型AuNPs@PNIPAM复合粒子的制备及催化性能

Preparation and Catalytic Performance of Surface-covered AuNPs@PNIPAM Composite Particles

金纳米粒子(AuNPs)表面能高,在水中极易团聚,使其应用受限.本文采用物理共混法,将带有正电荷的温敏聚(N-异丙基丙烯酰胺)(PNIPAM)微凝胶与带负电荷的AuNPs混合,经自组装制备了微凝胶表面覆盖AuNPs的有机-金属复合粒子AuNPs@PNIPAM.该复合粒子不仅具有很好的分散稳定性,而且其粒子的分散液具有温度比色性,在25℃→50℃→25℃的温度变化过程中呈现“红→紫→红”的可逆颜色变化.通过对硝基苯酚(4-NP)的还原反应,研究了复合粒子的催化性能.结果表明,复合粒子具有受温度调控的催化能力,随温度升高催化性能呈现先降后升的趋势.与文献报道的类似材料相比, AuNPs@PNIPAM复合粒子同时具有温度比色性和催化性能.

Gold nanoparticles(AuNPs)with high surface energy are easy to agglomerate in water,which restricts their applications.In this study,poly(N-isopropyl acrylamide)(PNIPAM)microgel and AuNPs were combined by electrostatic interaction through physical blending method inorder to cause negative citrate-stabilized AuNPs absorbed on the surface of positive PNIPAM microgels.The prepared surface-covered AuNPs@PNIPAM particles not only have excellent dispersion stability,but also exhibit a temperature-dependent colorimetric property,showing a reversible change of“red→purple→red”during the temperature change of 25℃→50℃→25℃.In addition,the p-nitrophenol(4-NP)reduction reaction was used as the simulated catalytic reaction to examine the catalytic perfor⁃mance of AuNPs@PNIPAM.The results showed that the catalytic performance of AuNPs@PNIPAM first decreased and then increased with temperature.Compared to similar materials reported in the literature,the AuNPs@PNIPAM showed both temperature-colorimetric properties and catalytic performance.