共查询到20条相似文献,搜索用时 171 毫秒
1.
2.
3.
4.
《中国石油和化工标准与质量》2017,(20)
炭负载铂纳米晶加氢催化剂是纳米材料在精细化工行业的一项有价值的应用,其利用金属纳米晶非常大的比表面积实现催化剂的高活性,并利用金属纳米晶在活性炭上的有效负载实现了高选择性。本文将对前期已完成的炭负载铂纳米晶催化剂的实验室制备工作进行总结,并对制备样品进行结构表征。 相似文献
5.
6.
《精细化工原料及中间体》2015,(9)
<正>产品和技术简介:本技术是一种负载型纳米金属加氢催化剂的制备方法,该方法可获得分散度高的负载型纳米金属催化剂。此类催化剂所用金属包括钯、钌、铂、铑及镍。该制备方法简单,成本低,重复性好,绿色无污染,催化剂寿命长,活性高,分别适用于硝基,芳环,炔烃,酮,醛等选择性加氢反应。 相似文献
7.
8.
《化工技术与开发》2021,50(9)
以氯金酸为原料,用水热法制备了金纳米复合微粒用作载体材料,再采用浸渍离心法负载姜黄素,得到负载姜黄素的金纳米复合微粒。采用粒度分析仪、XRD、红外、热重等方法,对金纳米复合微粒进行形貌结构表征。结果表明,所制备的材料为表面聚集微小孔隙、平均粒径为250nm左右的微小Au复合颗粒。当料液比为1∶1、姜黄素的质量浓度为3mg·m L-1、载药时间为6h时,金纳米复合微粒对姜黄素的包封率和载药量最大,分别为11.01%和35.48%。体外缓释实验结果表明,姜黄素原料在6h的释放率为64%,而金纳米复合微粒在6h的药物释放率仅为4.9%,可见用水热法制备的纳米金复合微粒具有较好的载药及缓释性能。 相似文献
9.
聚苯胺改性负载型纳米二氧化钛的研究 总被引:1,自引:0,他引:1
采用悬浮聚合法制备聚苯乙烯微珠载体,通过矿化接枝技术将溶胶-凝胶法制备的纳米二氧化钛负载在微珠载体上,制成负载型纳米二氧化钛光催化剂。利用导电聚苯胺对负载型纳米二氧化钛光催化剂进行可见光改性研究,通过XRD,SEM等方法对负载型纳米二氧化钛光催化剂进行表征;通过光催化降解甲基橙实验评价了导电聚苯胺改性负载型纳米二氧化钛光催化剂在可见光条件下的光催化活性。实验结果表明:导电聚苯胺对负载型纳米二氧化钛光催化剂的改性,可有效改善负载型纳米二氧化钛光催化剂在可见光条件下的光催化性能,降解率提高了24.5%。 相似文献
10.
11.
甲醇在碳载纳米Pt电极上的电化学研究 总被引:1,自引:0,他引:1
应用循环伏安法制备了nano-Pt/GC修饰电极,优化了铂微粒在电极表面的沉积条件,并用扫描电子显微镜(SEM)和在硫酸中的循环伏安曲线对其进行了表征。结果表明铂微粒较为均匀地分散在玻碳电极表面,粒径约为140nm,电极具有很大的比表面积。循环伏安实验结果表明nano-Pt/GC电极对甲醇电氧化的催化活性明显高于铂片电极,在该修饰电极上甲醇正向扫描和反向扫描时的氧化峰电位分别是0.67V和0.49V,峰电流为61.00mA/cm2和50.50mA/cm2,分别是铂片电极上的3.13倍和3.10倍,有效地提高了金属铂的利用率,铂微粒在电极表面的最佳沉积条件是循环次数为100次和沉积速度为5mV/s。 相似文献
12.
13.
Yanhui Xu 《Electrochimica acta》2007,52(16):5140-5149
Pt nano-clusters (nano-Pt) have been selectively attached to the open ends and defect sites of mildly oxidized multi-wall carbon nanotubes (MWCNTs) on a glassy carbon electrode (GCE) by a cyclic voltammetry (CV) electrodeposition method. The nano-Pt functionalized MWCNTs were characterized by XPS, XRD, FE-SEM and electrochemical techniques. The catalytic activity of the nano-Pt functionalized MWCNTs were tested by an oxygen reduction reaction (ORR) and a methanol oxidation reaction (MOR). Taking the ORR as an example, we found that the electrocatalytic activity of the nano-Pt functionalized MWCNTs can be well tuned by varying the cycle number and the PtCl62− concentration of the deposition conditions. The average size of the nano-Pt was 123 nm, and it was constituted of nano-crystallite of an average size of 10.8 nm. Though the large nano-Pt particles (100-150 nm) were only attached on the open ends and defect sites of the MWCNTs, which were very different from the highly dispersed small Pt nanoparticles (<10 nm) on carbon nanotubes reported by other research groups. In our method, excellent electrocatalytic activity of the nano-Pt functionalized MWCNTs for ORR and MOR can be obtained. The mechanisms for nano-Pt deposition are proposed. 相似文献
14.
通过循环伏安法(CV)在玻碳(GC)表面电沉积出分布较为均匀的纳米Fe粒子,制得纳米Fe/GC,再经置换反应制得具有Fe核Pt壳结构的纳米粒子(纳米FePt/GC)。SEM图像显示,纳米Fe/GC和纳米FePt/GC表面粒子的形貌均呈立方体,且分布较为均匀。纳米FePt/GC对乙醇的氧化具有很高的电催化活性。相对于纳米Pt/GC催化剂,纳米FePt/GC催化剂的起始氧化电位(Ei)提前了0.044V;其对乙醇氧化的峰电流密度(jp)大约是纳米Pt/GC催化剂的2.16倍。 相似文献
15.
Hybrid nanocomposites containing Pt nanoparticles (nano-Pt) and poly(3-methylthiophene) (P3MT) nanorods at glassy carbon surfaces have been successfully prepared by use of an in situ cyclic voltammetry (CV) method. Field emission scanning electron microscope (FE-SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltagrams were used to characterize the properties of these nanocomposites. SEM images showed that nano-Pt were located on the surface of P3MT nanorods and that they formed a three-dimensional (3D) porous nanostructure. EIS and CV results demonstrated that these hybrid nanocomposites had good conductivities, and could accelerate the electron-transfer rates of redox ions. From the results of electrochemical oxidation of methanol and nitrite, we observed that this nanocomposite-modified electrode exhibited excellent electrocatalytic activity, which might be useful in biosensors and/or fuel cells. 相似文献
16.
A sensitive hydroxylamine sensor was developed based on electrodeposition of Pt nanoclusters on choline film modified glassy
carbon electrode (nano-Pt/Ch/GCE). The properties of the composites were characterized by field emission scanning electron
microscope, X-ray photoelectron spectroscopy, powder X-ray diffraction, and electrochemical investigations. The designed nano-Pt/Ch/GCE
showed a high sensing performance for hydroxylamine in a wide concentration ranges of 5.0 × 10−7–1.1 × 10−3 M and 1.1 × 10−3–19 × 10−3 M. The detection limit was 0.07 μM (s/n = 3). The proposed electrode presented excellent operational and storage stability for the determination of hydroxylamine.
Moreover, the sensor showed good sensitivity, selectivity, and reproducibility properties. All the results indicated the designed
sensor had a good potential application in the determination of hydroxylamine. 相似文献
17.
纳米TiO2-Pt修饰电极的制备、性能及应用 总被引:8,自引:1,他引:7
采用电化学合成法和电沉积法制备高活性钛基纳米TiO2-Pt(Ti/nano-TiO2-Pt)修饰电极,通过循环伏安法研究并比较了钛基纳米TiO2膜电极、纯Pt电极、Ti/nano-TiO2-Pt电极在H2SO4溶液中的电化学行为以及Ti/nano-TiO2-Pt电极对Mn2+氧化为Mn3+的电催化性能.结果表明纳米TiO2-Pt修饰电极对Mn2+的电氧化有高催化活性.Mn2+氧化峰电位为1.28 V(vs SCE),比纯Pt电极负移0.12 V;析氧电位为1.40 V,比纯Pt电极高0.08 V.Ti/nano-TiO2-Pt修饰电极催化性能优于纯Pt电极和纳米TiO2膜电极,非均相电解氧化效率可达90%以上.电解得到的Mn3+可一步氧化甘油为甘油醛,收率为96%. 相似文献
18.
19.
20.
副产盐酸解吸制氯化氢技术及应用 总被引:2,自引:0,他引:2
介绍了副产盐酸解吸制取氯化氢技术的应用背景及意义;叙述了盐酸常规解析、变压精馏和萃取精馏制取气态氯化氢的基本原理和工艺流程;对各种方法作了比较并说明了适用条件,对生产工艺、设备及材料的选择提出了建议;提出了副产盐酸解吸制取氯化氢应用的注意事项及改进建议. 相似文献