Optic and catalytic properties of gold nanoparticles tuned by homopolymers  

作　　者：CHEN Xi ZHAO DongYun ZHAO LiZhi AN YingLi MA RuJiang SHI LinQi HE QiJun CHEN Li 

机构地区：[1]Tianjin Key Laboratory of Fiber Modification and Functional Fiber,School of Materials Science and Chemical Engineering,Tianjin Polytech University,Tianjin 300160,China [2]Key Laboratory of Functional Polymer Materials,Ministry of Education,Institute of Polymer Chemistry,Nankai University,Tianjin 300071,China

出　　处：《Science China Chemistry》2009年第9期1372-1381,共10页中国科学（化学英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant No. 20774051);Program for New Century Excellent Talents in Universities;the Outstanding Youth Fund (Grant No. 50625310)

摘　　要：Gold nanoparticles (GNs) are prepared through in situ reduction using NaBH4 in the presence of homopolymer PDMAEMA. The sizes of the GNs can be adjusted by alternating the molar ratio of gold to DMAEMA. Pure PDMAEMA aqueous solution shows a phase-transition at 50°C at pH 10 and 25°C at pH 14, while PDMAEMA-supported GNs aqueous solution shows a phase-transition at 47°C at pH 10 because of the increasing hydrophobic property resulting from GNs. Due to the pH and temperature-responsible characteristics of PDMAEMA, the resulting PDMAEMA-supported GNs exhibit pH adjustable temperature-responsive characteristics in optic and catalytic aspects. Under an acidic condition (pH 2), the GNs show unchanged surface Plasmon absorbance with a peak of 518 nm in a temperature range from 20 to 65°C. Under a basic condition (pH 10), the GNs first show the same absorbance with a peak at 518 nm in a temperature range from 20 to 40°C, and then the absorbance red shifts from 518 to 545 nm as temperature increases from 40 to 65°C. When the GNs are used as catalysts to catalyze the reduction of p-nitrophenol, the catalytic activity can be adjusted by changing the permeation of reactants in the PDMAEMA layer at low and high temperatures, respectively.Gold nanoparticles (GNs) are prepared through in situ reduction using NaBH4 in the presence of homopolymer PDMAEMA. The sizes of the GNs can be adjusted by alternating the molar ratio of gold to DMAEMA. Pure PDMAEMA aqueous solution shows a phase-transition at 50℃ at pH 10 and 25℃ at pH 14, while PDMAEMA-supported GNs aqueous solution shows a phase-transition at 47℃ at pH 10 because of the increasing hydrophobic property resulting from GNs. Due to the pH and tempera-ture-responsible characteristics of PDMAEMA, the resulting PDMAEMA-supported GNs exhibit pH adjustable temperature-responsive characteristics in optic and catalytic aspects. Under an acidic condi-tion (pH 2), the GNs show unchanged surface Plasmon absorbance with a peak of 518 nm in a tem-perature range from 20 to 65℃. Under a basic condition (pH 10), the GNs first show the same absorb-ance with a peak at 518 nm in a temperature range from 20 to 40℃, and then the absorbance red shifts from 518 to 545 nm as temperature increases from 40 to 65℃. When the GNs are used as catalysts to catalyze the reduction of p-nitrophenol, the catalytic activity can be adjusted by changing the permeation of reactants in the PDMAEMA layer at low and high temperatures, respectively.

关 键 词：GOLD nanoparticles catalyst HOMOPOLYMER 

分 类 号：O643.36[理学—物理化学]