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1.
SnO2纳米粒子的制备与表面改性   总被引:2,自引:1,他引:1  
以SnCl4·5H2O和氨水为原料,用水热法制备了粒度均匀的SnO2纳米粒子,并用γ-氨丙基三乙氧基硅烷(KH-550)对其进行了表面改性. 用X射线衍射(XRD)、透射电子显微镜(TEM)、纳米粒度/Zeta电位测定和元素分析测试技术对粒子进行了表征. 研究结果表明,所制得的SnO2纳米粒子为四方晶系金红石型结构,改性后的纳米粒子均一性进一步提高,粒径分布在8~20 nm,能形成稳定的分散体系.  相似文献   

2.
TiO_2纳米粒子的表面修饰研究   总被引:1,自引:0,他引:1  
利用表面修饰法合成了油酸 (OA)修饰的TiO2 纳米粒子 ,采用红外光谱 (IR)、透射电子显微镜 (TEM)和X射线光电子能谱 (XPS)对表面修饰的TiO2 纳米粒子进行了结构表征 ,并研究了油酸浓度对TiO2 表面覆盖量及在油中分散性能的影响 .研究结果表明通过油酸表面修饰 ,成功合成了具有油分散性能的纳米TiO2 ,并且获得了油酸修饰量与TiO2 的最佳配比 .  相似文献   

3.
表面修饰二氧化钛纳米粒子的结构表征及形成机理   总被引:59,自引:0,他引:59  
利用溶胶 凝胶法在混合溶剂中制备了硬脂酸表面修饰TiO2纳米粒子,对所合成的纳米粒子通过FTIR、XPS、XRD和TEM对其结构进行表征.结果确证了表面有机修饰层的存在,并且是羧酸根与无机内核以双齿配位形式结合;无机纳米内核的结晶度很低,但是可以确定为锐钛矿成分,平均粒径约为6~8 nm.提出了表面修饰纳米粒子的形成机理,认为在体系中硬脂酸和水之间发生竞争反应,其过程类似于聚合 阻聚反应,最后给出了硬脂酸表面修饰TiO2纳米粒子的结构模型.  相似文献   

4.
提出了一种简便易行的对磁性纳米粒子表面进行氨基化的方法. 首先使用化学共沉淀法合成了粒径为10 nm左右的Fe3O4纳米粒子, 然后用阿仑膦酸钠对其表面进行修饰, 使其表面具有了功能化的氨基. 利用透射电子显微镜(TEM)、X射线衍射(XRD)、振动样品磁强计(VSM)、动态光散射(DLS)仪、热重分析(TGA)仪、傅里叶变换红外(FT-IR)光谱仪、X射线光电子能谱(XPS)仪等对其进行表征. 结果显示磁性纳米粒子表面被成功地修饰了一层双膦酸分子. 所制备的纳米粒子可在pH=6.3稳定存在4周以上.  相似文献   

5.
提出了一种简便易行的对磁性纳米粒子表面进行氨基化的方法.首先使用化学共沉淀法合成了粒径为10 nm左右的Fe_3O_4纳米粒子,然后用阿仑膦酸钠对其表面进行修饰,使其表面具有了功能化的氨基.利用透射电子显微镜(TEM)、X射线衍射(XRD)、振动样品磁强计(VSM)、动态光散射(DLS)仪、热重分析(TGA)仪、傅里叶变换红外(FT-IR)光谱仪、X射线光电子能谱(XPS)仪等对其进行表征.结果显示磁性纳米粒子表面被成功地修饰了一层双膦酸分子.所制备的纳米粒子可在pH=6.3稳定存在4周以上.  相似文献   

6.
TiO_2纳米粒子的表面修饰研究   总被引:22,自引:0,他引:22  
李宗威  朱永法 《化学学报》2003,61(9):1484-1487
利用表面修饰法合成了油酸(OA)修饰的TiO_2纳米粒子,采用红外光谱(IR )、透射电子显微镜(TEM)和X射线光电子能谱(XPS)对表面修饰的TiO_2纳米粒 子进行了结构表征,并研究了油酸浓度对TiO_2表面覆盖量及在油中分散性能的影 响。研究结果表明通过油酸表面修饰,成功合成了具有油分散性能的纳米TiO_2, 并且获得了油酸修饰量与TiO_2的最佳配比。  相似文献   

7.
SnO2-TiO2薄膜载体对Au-Pt纳米颗粒电化学性能的影响   总被引:1,自引:1,他引:0  
采用真空镀膜法在玻碳(GC)电极表面修饰SnO2-TiO2薄膜, 在SnO2-TiO2/GC复合电极表面组装Au-Pt双金属纳米颗粒, 制得Au-Pt/SnO2-TiO2/GC复合电极. 通过循环伏安法(CV)研究了SnO2-TiO2薄膜载体对Au-Pt双金属纳米颗粒电化学性能的影响; 采用扫描电镜(SEM)及X射线光电子能谱(XPS)对Au-Pt在SnO2-TiO2薄膜沉积的形貌及结构进行了表征. 研究结果表明, 10 nm的Au-Pt双金属纳米颗粒均匀地组装于SnO2-TiO2薄膜表面; SnO2-TiO2薄膜载体改善了复合电极抗CO中毒能力; Au-Pt双金属合金的形成提高了Pt 对甲醇氧化的电催化能力, SnO2-TiO2薄膜载体又使Pt纳米粒子d空轨道增多, 提高了Au-Pt双金属纳米颗粒的稳定性和催化性能.  相似文献   

8.
在氨水的负催化作用下, 用酒石酸氢铵作模板剂, 原硅酸四乙酯(TEOS)经水解、缩聚, 生成SiO2纳米管. 利用硅烷偶联剂KH-570对SiO2纳米管进行表面修饰, 将乙烯基(-CH=CH2)引入SiO2纳米管表面, 改善其表面功能性. 通过扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)和傅立叶红外(FT-IR)等分析测试手段研究了SiO2纳米管的形貌结构及其表面修饰性能. 结果表明: 溶液的pH值是影响SiO2纳米管形貌的最主要因素, 最合适的酸碱度是4.5≤pH≤5.0; 纳米管平均外径300 nm, 内径100 nm, 长度10 µm以上, 管径均匀, 管壁表面光滑平坦, 没有出现裂纹等缺陷, 为无定形结构. KH-570功能修饰前后的纳米管形貌没有发生任何变化.  相似文献   

9.
低分子量氯磺化聚乙烯对纳米Si3N4粉体表面处理   总被引:2,自引:0,他引:2  
用降解氯磺化聚乙烯橡胶(CSM)的方法制备了低分子量氯磺化聚乙烯(LMCSM),将其作大分子表面改性剂对纳米氮化硅(Si3N4)粉体进行表面修饰,对改性前后的纳米Si3N4粉体采用沉降实验、FT-IR、TEM、TGA等方法进行了表征. 结果表明,LMCSM对纳米Si3N4粉体的改性主要为化学改性,其化学利用率为54%,物理利用率为29%;改性后的纳米Si3N4粉体的表面自由能从142.6 J/M2降至66.89 J/M2,在三氯甲烷中分散良好.  相似文献   

10.
用硫脲分子表面修饰的CdS纳米粒子的合成和表征   总被引:15,自引:0,他引:15  
报道了用硫脲分子进行表面化学修饰的CdS纳米粒子的合成方法,并引入了AOT(磺基琥珀酸双-2-乙基己基酯钠盐)作为平衡反离子,进一步对CdS表面作了修饰,增加了CdS纳米粒子在有机溶剂中的稳定性和可分散性。我们还探讨了温度、浓度、pH等因素对合成的影响,并通过TEM、XRD、FT-IR等手段对产物结构进行了表征。所得微粒粒径为5 nm左右,呈球形,硫脲分子与CdS纳米粒子富Cd2+表面通过形成Cd-S配位键而修饰在粒子表面。这种表面修饰的CdS纳米粒子将在非线性光学及自组装方面具有优  相似文献   

11.
Russian Journal of Physical Chemistry A - Amphiphilic zinc oxide (ZnO) was successfully prepared by modifing neat ZnO with silane coupling reagent KH-570. The modified ZnO and neat ZnO were...  相似文献   

12.
硅铝氧化物二元包覆钛白粉颗粒的有机改性   总被引:18,自引:0,他引:18  
在二元包覆SiO2,Al2O3薄膜的基础上,用钛酸酯偶联剂、硅烷偶联剂及三乙醇胺、季戊四醇对亚微米TiO2颗粒表面进行有机改性.考察了改性条件对颗粒表面改性结果的影响.通过疏水性试验和润湿性试验对改性前后TiO2颗粒的表面特性进行了表征.高温裂解色谱、热重分析、X光电子能谱的测试结果表明,不同改性剂与颗粒表面存在不同程度的化学键合作用.分析了改性剂在颗粒表面的包覆状态与结构.  相似文献   

13.
The composite film of nanometer AgO2/silane coupling reagent aminopropyltriethoxy-silane (CH3O)3Si(CH2)3NH2was prepared on single-crystal silicon by the self-assembly of silane on the hydroxylated substrate followed with the deposition of nanometer AgO2 on the silane SAMs from an aqueous Ag2O gel. The resultant composite film was characterized by means of X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The contact angles of distilled water on the silane SAMs and the composite film were measured to compare the surface states. The experiment shows that the nanometer Ag2O can be easily incorporated in the silane SAMs and lead to changed surface state of the composite film. Nanometer Ag2O crystallites in a size of about 20 nm distribute quite uniformly in the composite film. It was anticipated that the composite film might find application to the protection of single-crystal Si substrate in MEMS devices and also propose a novel single electron device structure based on nanoscale Ag2O colloidal particles.  相似文献   

14.
纳米TiO2有机表面改性的研究   总被引:26,自引:0,他引:26  
利用硅烷偶联剂(KH-550)对表面包覆氧化硅的金红石相纳米TiO2进行了有机表面改性。采用红外光谱(IR)、X射线光电子能谱(XPS)、热分析(TG-DTA)、BET、透射电镜(TEM)、润湿性和分散性实验等对表面改性前后的纳米TiO2进行了表征。红外光谱和X射线光电子能谱表明,KH-550以化学键合的方式结合在纳米TiO2的表面,并形成了有机包覆层。经测量,纳米TiO2表面的KH-550的质量分数约为2.0%。讨论了产生KH-550理论包覆量与实际包覆量差异的原因。TEM、TG和BET得出的结果显示,在纳米TiO2有机表面改性过程中存在明显的团聚现象,改进分散纳米TiO2的方法是提高有机改性效果的关键。润湿性实验和分散性实验表明,经KH-550表面改性的纳米TiO2同时具有亲水性和亲油性。  相似文献   

15.
Grafting silicon wafers with CH(3)O(CH(2)CH(2)O)(n)C(3)H(6)-trimethoxysilane and -trichlorosilane (n=6 to 9) was performed in different conditions (solvent, reaction time, washing) in order to select procedures compatible with the design of nanostructured surfaces for biomaterial applications, using electron-beam lithography. After a first screening by principal component analysis (PCA), the X-ray photoelectron spectroscopy (XPS) data were analyzed by plotting the carbon to oxygen molar ratio vs the molar ratio of carbon singly bound to oxygen [CO] over carbon bound only to carbon and hydrogen [C(C,H)]. This was found to be a convenient method for discarding samples containing free polymerized silane. Such excess occurred as a result of insufficient washing or unsuitable solvent for the reaction (ether), as confirmed by AFM and thickness measured by X-ray reflectometry. Angle resolved XPS analysis indicated that the grafted silane layer had a 1-2 nm thickness and was covered by a thin layer of adventitious contaminant. As a result, the surface chemical composition obtained covered a broad range (O/C of 0.4 to 1.1; CO/C(C,H) of 2.5 to 6.5); variations could not be related to the nature of the silane reagent and no significant difference was found between hexane and toluene as solvent for the reaction. The grafted silane layer was not stable upon incubation during 24 h in phosphate buffered saline (PBS) at 37 degrees C, which mimics biological environments. As a consequence, the grafted wafers did not show protein repellent properties. This alteration was not observed at room temperature. XPS analysis demonstrated that silane layer detachment was due to a hydrolysis within the SiO(2) layer initially present at the wafer surface.  相似文献   

16.
The organic nano-TiO2 was synthesized in reverse (W/O) microemulsion, using tetrabutyl titanate (TBOT) as precursor and γ-methacryloxypropyl trimethoxy silane (KH-570) as modifier. After phase inversion from W/O microemulsion to oil-in-water (O/W) emulsion, nano-TiO2/poly(methyl methacrylate) hybrid latex was prepared via in-situ polymerization based on the O/W emulsion containing organic nano-TiO2. Fourier transform infrared spectroscopy (FTIR) indicated that KH-570 was successfully grafted onto the surface of TiO2 particles. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) demonstrated that the average diameter of nano-TiO2 was about 10 nm and the hybrid latex had obvious core-shell structure with particle size of 155 nm. The TBOT content and the mass ratio of KH-570 to TOBT have important effect on the polymerization stability and storage stability of the hybrid latex. When the TBOT content was 5% and the mass ratio of KH-570 to TOBT was 0.6, the coagulation rate (Cr) was 3.0% and the zeta potential reached 36.1 mV. The possible formation mechanism of the hybrid latex was also proposed.  相似文献   

17.
通过溶胶-凝胶法制得平均粒径为226 nm形状规整的球形二氧化硅微球.用硅烷偶联剂KH-570作表面处理后,使用十二烷基硫酸钠作为乳化剂,采用超声化学的方法,将纳米级二氧化硅组装包覆在三聚氰胺甲醛树脂表面,形成具有高比表面积的微米级颗粒.通过红外光谱FT-IR、扫描电子显微镜、激光粒度测试等方法对二氧化硅及组装颗粒进行表征,并对合成机理进行分析.发现二氧化硅在三聚氰胺甲醛树脂颗粒上均匀包覆,最后包覆物粒径分布较均一,平均粒径为30 μm.  相似文献   

18.
采用谷氨酸与硅烷偶联剂(KH-792)缩合反应,制备出一种含酰胺基的硅烷偶联剂,利用其与材料之间的化学结合,将谷氨酸共价固定至磷灰石-硅灰石生物玻璃陶瓷表面,实现表面改性。将改性后的磷灰石-硅灰石生物玻璃陶瓷与人骨肉瘤细胞MG63共培养,评价其体外细胞生物相容性。应用FTIR、SEM、XPS等测试技术分别对合成的偶联剂、改性后的陶瓷材料进行结构、表面形貌及细胞生长情况的表征,结果表明:谷氨酸与KH-792的反应产物有酰胺基生成;含酰胺基的硅烷偶联剂能对磷灰石-硅灰石生物玻璃陶瓷表面进行有效改性;共培养3 d后细胞在材料材料表面大量贴附,MTT实验也证明增殖良好,即含酰胺基的硅烷偶联剂能改善磷灰石-硅灰石生物玻璃陶瓷的体外细胞生物相容性。  相似文献   

19.
This paper aims to investigate the mechanical behaviors of carbon fiber-reinforced PEEK-Titanium hybrid laminates (TiGr) prepared by different surface treatment conditions using silane coupling agent. In order to improve the bonding performance between the titanium sheets and PEEK, the titanium layers were subjected to sandblasting roughening and silanization treatment, the curing process was explored by setting different concentrations of silane coupling agent, curing temperatures and curing times. The optimum parameters of the process were determined by analyzing the mechanical properties of the laminates, which are 10% of SCA concentration, 130 °C of curing temperature and 1 h of curing time, and the corresponding tensile, bending and inter-laminar shearing strengths are 837, 1071 and 75 MPa, respectively. The surface composition, structures and chemical bonding of the modified titanium sheet were analyzed through Scanning Electronic Microscope (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). It was evidenced that the optimal process could produce a relatively complete and uniformed silane film compared to other cases. In addition, the results show that the Si–O–Ti covalent bonds were formed, which demonstrated that the preparation of the laminates through silane coupling agent is reliable.  相似文献   

20.
聚乙酰亚胺涂敷单晶硅表面上全氟亏酸单层膜   总被引:8,自引:1,他引:7  
Ultra-thin film of perfluorodecanoic acid expected to be excellent lubricant for micro-machines was prepared successfully on single crystal silicon substrate.The film was characterized by means of X-ray photoelectron spectroscopy (XPS) and contact-angle meter.The chemical reaction involved in the preparation of the ultra-thin film was discussed as well.After being immersed in a dilute aqueous solution of polyethyleneimine (PEI) for 15 minutes and rinsed with distilled water,the silicon substrate was coated with a thin film of PEI,which was then put into a dilute solution (1× 10- 3 mol· L- 1) of perfluorodecanoic acid in hexadecane.Subsequently the steady perfluorodecanoic acid ultra-thin film was developed on PEI coating in the presence of a covalent amide bond between carboxylic group and the primary or secondary amine groups of PEI.This process was accompanied by the contact angle changes of water droplet on the Si surface (see Table 1).Moreover,the reaction between perfluorodecanoic acid and PEI was significantly influenced by N,N′ -dicyclohexylcarbodiimide (DCCD).The contact angle on the ultra-thin film of perfluorodecanoic acid is only 66.3° in the absence of DCCD in the reacting solution; it rises to 89.4° in the presence of DCCD.This indicates that the reaction between perfluorodecanoic acid and PEI was accelerated by DCCD,and the quality of perfluorodecanoic acid ultra-thin film thus improved.XPS analysis of the ultra-thin film indicates that the derivatization of PEI with perfluorodecanoic acid was accompanied by several changes.First,a large and highly symmetrical F 1s peak appeared at 688.3 eV (C- F*).Secondly,a new peak of N 1s appeared at 400.7 eV (chemical shift 1.4 eV),which was attributed to the N atom attached to the carbonyl group (O=C- N*).Thirdly,three new peaks of C 1s appeared at 286.1 eV (chemical shift 1.5 eV),288.1 eV (chemical shift 3.5 eV),and 291.0 eV (chemical shift 5.4 eV),respectively.These C 1s peaks were attributed to the C atom attached to the O=C- N group (O=C- N- C*),the carboxyl C atom (O=C*- N),and the C atom in - CF3 group (C*- F),respectively.Therefore it can be concluded that perfluorodecanoic acid has been chemically adsorbed onto the surface of PEI and perfluorodecanoic acid ultra-thin film prepared successfully.  相似文献   

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