One-step synthesis of monodisperse polydopamine-coated silver core-shell nanostructures for enhanced photocatalysis
One-step synthesis of monodisperse polydopamine-coated silver core-shell nanostructures for enhanced photocatalysis
复制标题
一步合成单分散聚多巴胺包覆的银核壳纳米结构以增强光催化作用
DOI：
10.1039/c1nj20850k
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发表时间：
2012-01-01
影响因子：
3.3
通讯作者：
Chen, Jian-Rong
中科院分区：
文献类型：
--
作者：
Feng, Jiu-Ju;Zhang, Pei-Pei;Chen, Jian-Rong
以银离子为氧化剂，通过一步聚合法制备了纳米银（Ag）/聚多巴胺（PDA）复合材料。多巴胺的氧化和银离子的还原同时发生在一个步骤中，这导致了一个明确的核壳结构的PDA涂层周围的银纳米粒子（AgNPs）。采用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、X射线粉末衍射（XRD）、紫外-可见光谱（UV-vis）、傅里叶变换红外光谱（FT-IR）、循环伏安（CV）和电化学阻抗谱（EIS）等方法对样品的形貌、结构和组成进行了表征。该复合材料在紫外光照射下对中性红具有良好的光催化降解性能。对等离子体激元诱导的光化学反应的可能机制进行了详细的讨论，其中AgNPs表面的主要活性物种O-2（中心点-）参与了该光反应体系。由于紫外光下π-π * 电子跃迁的存在，PDA壳层大大提高了介电常数。
Nanosized silver (Ag) and polydopamine (PDA) composite was prepared via one-step polymerization of dopamine, using Ag+ ion as an oxidant. The oxidization of dopamine and the reduction of Ag+ ion occurred simultaneously in one-step, which resulted in a well-defined core shell structure of PDA coating around the Ag nanoparticles (AgNPs). Its morphology, structure, and composition were characterized by scanning electron microscopy (S EM), transmission electron microscopy (TEM), X-ray power diffraction (XRD), UV-vis, Fourier transform infrared (FT-IR) spectroscopy, cyclic voltammograms (CVs) and electrochemical impedance spectroscopy (EIS), respectively. The composite showed good performance toward the photo-catalytic degradation of neutral red under UV irradiation. The possible mechanism regarding the plasmon-induced photocatalysis was discussed in some detail, where the main active species of O-2(center dot-) on the surface of the AgNPs were involved in this photoreaction system. The PDA shells greatly improve the photocatalysis due to the existence of the pi-pi* electron transition under UV light.