碳纤维纸负载纳米Pd-Au的绿色合成工艺及催化析氢应用

发布时间：2018-05-18 05:41

本文选题：双金属纳米材料 + 碳纤维纸　；参考：《福建师范大学》2015年硕士论文

【摘要】：双金属纳米材料具有卓越的催化活性及稳定性,近年来在电解水析氢方向得到了广泛关注。目前双金属催化电极的制备工艺成本高昂且非环境友好,限制了其大规模化应用。本研究从绿色化工角度出发,利用福建省本土速生植物桉树树叶作为制备催化电极的还原剂及保护剂,结合以浸渍方式为主的静电自组装技术,发展了一种操作简易、绿色环保的新型制备工艺,成功将双金属纳米颗粒负载到具有三维复杂结构的基底上,制备得到碳纤维纸负载纳米钯金电极,同时实现了对催化剂组成及结构的精准调控。通过扫描电镜、X射线能谱、扫描透射电镜、X射线光电子能谱等物理表征方法发现,制备得到的纳米颗粒形貌统一,为近球形,平均粒径在180 nm左右,均匀分散在碳纤维表面,催化剂负载量约为0.5 mg/cm2;纳米颗粒中钯金的摩尔比例基本接近前驱体比例,原子排列方式为混合式,具有完整的晶体结构和高结晶度。通过极化曲线、计时电流、电化学阻抗谱和双电层电容分析等电化学测试手段发现,负载型纳米钯金电极表现出优异的催化析氢活性,具有较低的塔菲尔斜率(47 mV/dec)和较高的交换电流密度(0.256 mA/cm2);此外,电极具有良好的稳定性,在高工作强度和长时间尺度的催化反应后,析氢活性保持基本不变。在实验室小试的基础上,根据工艺特性和产品质量要求,合理设计了制备500×500mm2碳纤维纸负载纳米钯金电极的中试生产方案,并完成了工艺设备选型、车间平面设计及经济效益可行性分析,为下一步准备中试生产催化电极做出了初步的设计构想。该新型制备工艺的发展不仅为制备电解水析氢电极提供了一个高效环保的新方法,也为其他电化学催化设备的建构提供了新思路。
[Abstract]:Bimetallic nanomaterials with excellent catalytic activity and stability have attracted wide attention in the direction of hydrogen evolution in electrolytic water in recent years. The large scale application of bimetallic catalytic electrode is limited due to its high cost and non-environmental friendliness. From the point of view of green chemical industry, using the leaves of native fast growing eucalyptus in Fujian Province as reducing agent and protective agent for preparing catalytic electrode, and combining with electrostatic self-assembly technology with impregnation method, a simple and easy operation was developed. The novel green preparation technology successfully loaded bimetallic nanoparticles onto the substrates with three dimensional complex structure and prepared carbon fiber paper loaded nano-palladium gold electrode. At the same time the precise control of the composition and structure of the catalyst was realized. By means of SEM X-ray spectroscopy, SEM X-ray photoelectron spectroscopy and other physical characterization methods, it was found that the morphology of the prepared nanoparticles was uniform, nearly spherical, the average particle size was about 180 nm, and the nanoparticles were uniformly dispersed on the surface of carbon fiber. The amount of catalyst supported is about 0.5 mg / cm ~ 2. The molar ratio of palladium and gold in the nanoparticles is close to that of the precursor, and the atom arrangement is mixed, with complete crystal structure and high crystallinity. By means of polarization curve, chronoelectric current, electrochemical impedance spectroscopy and double layer capacitance analysis, it was found that the supported nanocrystalline palladium gold electrode showed excellent catalytic hydrogen evolution activity. The electrode has a low Taffel slope of 47 MV / cm ~ (2) and a high exchange current density of 0.256 Ma / cm ~ (2). In addition, the electrode has good stability, and the activity of hydrogen evolution remains basically unchanged after high working intensity and long time scale catalytic reaction. On the basis of laboratory test, according to the process characteristics and product quality requirements, the pilot production scheme of preparing 500 脳 500mm2 carbon fiber paper loaded nano-palladium gold electrode was designed, and the selection of process equipment was completed. The plane design of workshop and the feasibility analysis of economic benefit are discussed, and a preliminary design conception is made for the pilot-scale production of catalytic electrode. The development of the new preparation process not only provides a new method of high efficiency and environmental protection for the preparation of electrolytic hydrogen evolution electrode, but also provides a new idea for the construction of other electrochemical catalytic equipment.
【学位授予单位】：福建师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ116.2;TB383.1

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