Optic and catalytic properties of gold nanoparticles tuned by homopolymers
Optic and catalytic properties of gold nanoparticles tuned by homopolymers
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DOI：
10.1007/s11426-009-0154-4
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发表时间：
2009-09
影响因子：
9.6
通讯作者：
Xi Chen;Dongyu Zhao;Lizhi Zhao;Yingli An;Rujiang Ma;Linqi Shi;Qi He;Li Chen
中科院分区：
文献类型：
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作者：
Xi Chen;Dongyu Zhao;Lizhi Zhao;Yingli An;Rujiang Ma;Linqi Shi;Qi He;Li Chen
在均聚物PDMAEMA存在下，以NaBH 4为还原剂，通过原位还原法制备了金纳米粒子（GNs）。GN的尺寸可以通过改变金与DMAEMA的摩尔比来调节。纯PDMAEMA水溶液在pH 10下在50°C和在pH 14下在25°C下显示相变，而PDMAEMA负载的GN水溶液在pH 10下在47°C下显示相变，这是因为GN导致的疏水性增加。由于PDMAEMA的pH和温度响应特性，所得的PDMAEMA负载的GN在光学和催化方面表现出pH可调的温度响应特性。在酸性条件（pH 2）下，GN在20至65°C的温度范围内显示出在518 nm处具有峰的不变的表面等离子体吸光度。在碱性条件下（pH 10），GN首先在20至40°C的温度范围内显示出相同的吸光度，在518 nm处具有峰，然后随着温度从40 ° C升高至65°C，吸光度从518 nm红移至545 nm。当GNs作为催化剂用于催化还原对硝基苯酚时，催化活性可以通过分别在低温和高温下改变反应物在PDMAEMA层中的渗透来调节。
Gold nanoparticles (GNs) are prepared throughin situreduction using NaBH4in 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 ofp-nitrophenol, the catalytic activity can be adjusted by changing the permeation of reactants in the PDMAEMA layer at low and high temperatures, respectively.