Surface modification of TiO2 nanoparticles with silane coupling agents
Surface modification of TiO2 nanoparticles with silane coupling agents
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DOI：
10.1016/j.colsurfa.2011.11.033
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发表时间：
2012-11-05
影响因子：
5.2
通讯作者：
Dutschk, Victoria
中科院分区：
文献类型：
--
作者：
Zhao, Jie;Milanova, Maria;Dutschk, Victoria
由于其优异的光催化活性使得TiO 2纳米颗粒可用作自清洁剂和抗菌剂，以及用于紫外线防护和环境净化，因此被认为具有通过TiO 2纳米颗粒实现织物多功能化的巨大潜力。为了提高纳米粒子在织物表面的耐久性，采用3-氨丙基三甲氧基硅烷（APTMS）和3-异氰酸基丙基三甲氧基硅烷（IPTMS）对商品化纳米TiO 2粒子进行了表面改性。采用热重分析法对不同反应条件下的接枝效率进行了评价。FTIR光谱证实，APTMS接枝的TiO 2纳米粒子（A-TiO 2）和IPTMS接枝的TiO 2纳米粒子（I-TiO 2）表面均通过Ti-O-Si化学键成功接枝了有机官能团。纳米TiO 2表面改性后，纳米粒子的等电点（IEP）从pH 6.4左右移动到pH 9.4左右，Zeta电位平台显著增加，这是由于酸性区域的-NH 2基团质子化所致。颗粒流体动力学直径和多分散指数（PDI）的显着降低表明颗粒分散稳定性受到颗粒zeta电位增加的积极影响。随着有机硅烷比率从0重量%至200重量%，结果表明，A-TiO_2光催化活性的速率常数略有下降，而I-TiO_2则迅速下降，这与接枝效率密切相关。(C)2011 Elsevier B. V.保留所有权利。
Due to their excellent photo-catalytic activities making TiO2 nanoparticles applicable as self-cleaning and anti-bacterial agents, as well as for UV protection and environmental purification, a great potential for multi-functionalization of fabrics by TiO2 nanoparticles is considered. In order to improve the durability of nanoparticles at a fabric surface, the surface of commercial TiO2 nanoparticles was modified by 3-aminopropyltrimethoxysilane (APTMS) and 3-Isocyanatopropyltrimethoxysilane (IPTMS) by an aqueous process in this study. The grafting efficiency of agents to TiO2 nanoparticles at different reaction conditions was estimated by thermal gravimetric analysis. FTIR spectra confirmed that organic functional groups were successfully grafted onto the TiO2 nanoparticles surface both for APTMS-grafted TiO2 nanoparticles (A-TiO2) and IPTMS-grafted TiO2 nanoparticles (I-TiO2) through Ti-O-Si chemical bonds. After the surface modification of TiO2 nanoparticles, isoelectric point (IEP) of nanoparticles was shifted approximately from pH 6.4 to pH 9.4 and the zeta potential plateaus increased significantly which was explained by the protonation of -NH2 groups in the acidic region. The significant reduction of particle hydrodynamic diameters and polydispersity index (PDI) indicated the particle dispersion stability was positively affected by an increase in particle zeta potential. With increasing the organosilane ratio from 0 wt.% to 200 wt.%, a slight decline of the rate constant of A-TiO2 photocatalytic activity and a rapid decrease for I-TiO2 were revealed, which was significantly dependent on the grafting efficiency. (C) 2011 Elsevier B.V. All rights reserved.