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以利用静电纺丝技术制备的TiO2纳米纤维为模板和反应物,原位水热合成了具有异质结构的SrTiO3/TiO2复合纳米纤维.采用X射线衍射(XRD)、扫描电子显微镜(SEM)、能量散射光谱(EDS)、高分辨透射电子显微镜( HRTEM)和X射线光电子能谱(XPS)等测试手段对样品的结构和形貌进行了表征.用罗丹明B(RB)模... 相似文献
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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
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制备了两种器外预硫化型MoNiP/γ-Al2O3催化剂,并以二苯并噻吩为模型化合物考察了其加氢脱硫(HDS)活性,选择了传统的器内预硫化催化剂作为参比. 采用X射线衍射(XRD)、 高分辨透射电镜(HRTEM)和X射线光电子能谱(XPS)等手段对二者在加氢活性相方面的差别进行了研究. 结果表明,器外预硫化催化剂的HDS活性(最高达到99%)与器内预硫化催化剂相当,但是其加氢能力相对较弱. XRD与HRTEM等研究表明,器外预硫化催化剂所形成的MoS2片晶的堆垛层数相对较低,而Mo与S元素的XPS分析结果则说明相对器内预硫化催化剂,器外预硫化催化剂中不但Mo的硫化度较低,而且MoS2活性相的含量亦较少,而二者活性相之间的这种差异应是导致两类催化剂加氢活性不同的主要原因. 相似文献
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利用电子自旋共振谱(ESR)和X射线光电子谱(XPS)研究了MoS2摩擦表面的氧化行为和摩擦表面氧化的电子转移,发现MoS2在摩擦失效过程中Mo4+与氧作用生成稳定的Mo6+终态氧化物,其间经过Mo5+过渡态。深入揭示了MoS2摩擦表面氧化过程的复杂性,指出Mo在摩擦表面氧化过程中以多种化学状态存在,Mo原子的氧化是Mo4d轨道上的单电子转移过程。 相似文献
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采用低温硫化工艺和复分解反应制备了无臭硫化廿二酸,在四球摩擦磨损试验机上考察了其在菜籽油中的减摩抗磨行为及承载能力,并对钢球磨损表面进行了扫描电子显微(SEM)、电子探针(EPMA)以及X射线光电子能谱(XPS)分析。通过与廿二酸和硫化异丁烯的对比研究发现,在廿二酸中引入硫后,氧与硫产生了明显的协同减摩抗磨及承载作用。钢球磨损表面XPS分析结果表明,在摩擦过程中硫化廿二酸发生了摩擦化学变化,表面EPMA分析结果表明其表面保护膜富含氧和硫。 相似文献
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Carbon fabric (CF) was surface treated with silane-coupling agent modification, HNO3 oxidation, combined surface treatment, respectively. The friction and wear properties of the carbon fabric reinforced phenolic composites (CFP), sliding against GCr15 steel rings, were investigated on an M-2000 model ring-on-block test rig. Experimental results revealed that combined surface treatment largely reduced the friction and wear of the CFP composites. Scanning electron microscope (SEM) investigation of the worn surfaces of the CFP composites showed that combined surface modified CFP composite had the strongest interfacial adhesion and the smoothest worn surface under given load and sliding rate. SEM and X-ray photoelectron spectroscopy (XPS) study of carbon fiber surface showed that the fiber surface became rougher and the oxygen concentration increased greatly after combined surface treatment, which improved the adhesion between the fiber and the phenolic resin matrix and hence to improve the friction-reduction and anti-wear properties of the CFP composite. 相似文献
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用MS、 FT-IR等方法对合成的三正丁基一硫代及四硫代磷酸酯进行了结构表征,并在四球摩擦磨损试验机上考察了其在液体石蜡中的摩擦学性能;用扫描电镜(SEM)和X射线光电子能谱(XPS)对钢球磨痕表面做了分析.结果表明: 对于钢-钢摩擦副,合成的两种硫代磷酸酯可以显著提高液体石蜡的极压抗磨性能,但不能改善其减摩性能.钢球磨损表面XPS和SEM分析结果表明,添加剂分子在金属表面发生物理或化学吸附,并导致金属表面的腐蚀和摩擦化学反应. 相似文献
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将氟原子引入不饱和聚酯链中,合成了含氟不饱和聚酯,并探索了其合成条件;采用四球摩擦磨损试验机评价了含氟不饱和聚酯在液体石蜡中作为抗磨添加剂的摩擦学性能,并利用红外光谱仪、X射线光电子能谱仪和扫描电镜分析了摩擦表面膜的结构、形貌和化学状态.结果表明,氟原子的引入有利于降低聚酯的黏度,并改善聚酯在液体石蜡中的分散性;合成产物作为抗磨添加剂可以在钢球磨损表面形成聚合物膜,从而显著提高基础油的摩擦学性能. 相似文献
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二硫化钼中空微球的制备、表征以及光催化性能 总被引:3,自引:2,他引:1
以四丁基溴化铵为添加剂,采用水热法制备出直径为2~5μm的二硫化钼(MoS2)空心微球,研究了反应温度、添加剂量和时间对MoS2物相和形貌的影响。XRD、SEM、EDS、TEM、XPS表征结果表明,当反应温度为240℃时可得到结晶良好的六方相2H-MoS2,MoS2的形貌主要受四丁基溴化铵用量的影响,随着用量的增多MoS2历经了球状-花球状-不规则堆积状的递变。对MoS2中空微球的形成机制进行了探讨,认为在反应中四丁基溴化铵起到了模板的作用。通过制备样品对罗丹明B的降解评估了二硫化钼中空微球的光催化性能,其对罗丹明的降解效率达到90%。 相似文献
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Lu Chen Nan Tu Qianyang Wei Tao Liu Chengzhi Li Wenbo Wang Jianhui Li Hailin Lu 《Surface and interface analysis : SIA》2022,54(3):218-230
In this paper, graphene oxide/polyethylene glycol (GO/PEG) composite water-based lubricant was prepared by an ultrasonic dispersion method, and characterized and analyzed by Fourier transform infrared (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The suspension performance of GO/PEG composite water-based lubricant in water was verified by static sedimentation and centrifugation, and then, the prepared GO/PEG composite water-based lubricant was added into 304 stainless steel and 6061 aluminum alloy, and the coefficient of friction (COF) curve, average COF value, average wear rate, corresponding photomicrographs of balls and disks after wear, and energy-dispersive spectrometer (EDS) elemental analysis were used to illustrate the lubrication effect and lubrication mechanism. The results show that the GO/PEG composite water-based lubricant possesses excellent suspension ability in water, and the average COF value and wear rate of GO/PEG composite water-based lubricant are reduced by 78.8% and 88.8%, respectively, compared with water lubrication. The excellent lubrication effect of GO/PEG composite water-based lubricant can effectively reduce the cold-welding and adhesive wear phenomenon, mainly because GO/PEG composite water-based lubricant first fills the uneven surface of friction mating to form a high-quality lubricating film and then because of the special space structure of GO and the low shear between GO layers and the synergistic lubrication effect of GO/PEG. 相似文献
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在油酸钠/十六烷基溴化铵乳液体系中合成了表面修饰中空LaF3纳米微粒. 通过透射电子显微镜(TEM)、X射线衍射(XRD)、傅立叶变换红外光谱(FTIR)、热重分析(TG-DTG)、能谱分析(EDS)等测试手段对其结构和形貌进行了表征. 同时在四球摩擦磨损试验机上考察了LaF3纳米微粒作为润滑油添加剂时, 添加浓度和施加载荷对其抗磨减摩性能的影响. 结果表明, 此纳米微粒的表面为油酸修饰, 具有中空结构, 平均粒径约17.5 nm; 表面修饰中空油酸/三氟化镧纳米微粒作为成品润滑油的添加剂, 具有良好的抗磨性能. 另外, 对中空纳米微粒的形成机理进行了分析. 相似文献
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Synthesis of nanostructured lanthanum fluoborate modified by oleylamine and evaluation of its tribological properties as a lubricating additive in synthetic ester
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Fengjie Jin Guangbin Yang Shiyong Song Shengmao Zhang Laigui Yu Pingyu Zhang 《Surface and interface analysis : SIA》2016,48(10):1033-1039
Lanthanum fluoborate modified by oleylamine [denoted as La(BF4)3‐OA] was synthesized as a potential lubricant additive by direct precipitation method with sodium tetrafluoroborate and lanthanum nitrate [La(NO3)3] as the staring materials and oleylamine (OA) as the surface‐modifying agent in distilled water‐ethanol mixed solvent. The effects of reaction temperature, OA to La(NO3)3 ratio, and surfactant cetyltrimethyl ammonium bromide on the size and shape of as‐synthesized La(BF4)3‐OA were investigated. The crystalline structure and morphology of as‐obtained La(BF4)3‐OA were characterized by X‐ray diffraction, transmission electron microscopy, Fourier transform infrared spectrometry, and X‐ray photoelectron spectroscopy. Moreover, the tribological properties of La(BF4)3‐OA as an additive in dioctyl sebacate, a synthetic ester, were evaluated with a four‐ball machine, and the worn surfaces of the steel balls were analyzed with a field emission scanning electron microscope equipped with an energy dispersive spectrometer accessory. It was found that the as‐synthesized La(BF4)3‐OA exhibits disk‐like nanoflake shape and have a diameter of 10–45 nm, depending on varying synthetic conditions. As‐synthesized La(BF4)3‐OA as an additive in DIOS possesses excellent antiwear and friction‐reduction performance for the steel–steel pair, which is because the as‐synthesized additive simultaneously contain tribologically active elements La, B, and F that facilitate the formation of a boundary lubricating and protecting film on sliding steel surfaces thereby avoiding direct contact of the steel–steel pair and significantly reducing the friction and wear. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献