微生物燃料电池阴极催化剂双核酞菁钴的结构及性能优化

发布时间：2018-06-02 00:31

  本文选题：微生物燃料电池 + 双核酞菁钴　； 参考：《华南理工大学》2015年硕士论文

【摘要】：微生物燃料电池(microbial fuel cells,MFCs)是利用污水中微生物作为生物催化剂降解废水中有机物同时产生电能的装置。该技术在能源紧缺的二十一世纪具有巨大的潜在应用价值。在阴极,氧气因便宜易得且产物绿色环保,成为一种理想的电子受体。在实现氧气的还原反应按理想四电子还原方式进行的过程中,高性能阴极催化剂起着至关重要的作用。目前,研究使用最多的阴极催化剂为铂,然而很多化学物质(如HS-,C l-,CO)易引起铂催化剂中毒,并且价格昂贵,储量有限,限制了其大规模的商业化应用。因此高效廉价的氧还原催化剂对于MFCs的研究具有重要的理论和现实意义。本文以生活污水为研究对象,用碳布作阳极,以双核酞菁钴(Bi-Co Pc)系列作为阴极催化剂应用于单室空气阴极微生物燃料电池(SCMFC),对Bi-Co Pc进行结构优化,以期解决微生物燃料电池阴极催化剂性能差且价格昂贵的问题。本论文的具体研究结果概括如下:1)以Bi-Co Pc/C作为新型阴极催化剂,代替价格昂贵的Pt/C运用于微生物燃料电池,优化该系列催化剂电池反应条件,包括:催化剂用量、底物乙酸钠浓度、离子强度、p H值等最佳条件。当催化剂用量1 mg/cm2、底物乙酸钠浓度为2 g/L、氯化钠浓度为0.1 M、p H值为6时微生物燃料电池产电性能最好。2)Bi-Co Pc的结构优化:将N i O和Co O复合到Bi-Co Pc表面,形成双核酞菁钴复合物。将合成的Bi-Co Pc/C-Ni O和Bi-Co Pc/C-Co O催化剂与钴基催化剂Co Pc/C和Bi-Co Pc/C、氧化物催化剂Ni O和Co O作对比,并通过TEM、XPS对催化剂形貌和表面结构进行细致表征。XPS结果显示,Ni O和Co O可以提高催化剂中氧和氮官能团的含量。循环伏安和线性扫描伏安测试表明Bi-Co Pc/C-Ni O和Bi-Co Pc/C-Co O的氧还原峰位分别在-0.12 V和-0.22 V,优于未复合的Bi-Co Pc/C。采用Bi-Co Pc/C-Ni O和Bi-Co Pc/C-Co O作为阴极催化剂的SCMFC最大功率密度分别为400和368 m W/m2,接近于商用Pt/C的最大功率密度(450 m W/m2),研究结果表明复合催化剂Bi-Co Pc/C-Ni O和Bi-Co Pc/C-Co O有望替代商用Pt/C催化剂。3)详细研究了高温焙烧对Bi-Co Pc催化剂的结构和性能的影响。实验中采用的焙烧温度分别为300、600、800、1000 oC。用SEM、TEM、XPS、XRD等对催化剂形貌、表面组成和结构特征等进行表征,并用循环伏安和线性扫描伏安对其电催化活性进行测试。研究结果表明:在焙烧温度为800度时,Bi-Co Pc/C-800表现出最好的氧还原催化活性,这与Bi-Co Pc/C-800含有大量的吡咯型氮相关。所组装的SCMFC最大功率密度随焙烧温度变化关系为:Bi-Co Pc/C-800Bi-Co Pc/C-1000Bi-Co Pc/C-600Bi-Co Pc/C-300Bi-Co Pc/C,其中,Bi-Co Pc/C-800作为阴极催化剂的SCMFC产生的最大功率密度为604 m W/m2,仅比Pt/C(724 m W/m2)低17%。这表明Bi-Co Pc/C-800具有优良的电催化活性,可以期望替代Pt/C用于微生物燃料电池的阴极催化剂,使MFC大规模应用成为可能。
[Abstract]:Microbial fuel cells (MFCs) is a device which uses microorganisms in wastewater as biocatalysts to degrade organic matter and generate electric energy. This technology has great potential application value in the energy shortage 21 century. At the cathode, oxygen is an ideal electron receptor because it is cheap and environmentally friendly. High performance cathode catalyst plays an important role in the process of oxygen reduction by ideal four-electron reduction. At present, platinum is the most widely used cathodic catalyst. However, many chemical substances (such as HS-Cl-CoC) are prone to lead to platinum catalyst poisoning, and their large scale commercial applications are limited due to their high cost and limited reserves. Therefore, the efficient and cheap oxygen reduction catalyst has important theoretical and practical significance for the study of MFCs. In this paper, using carbon cloth as anode and binuclear cobalt phthalocyanine (Bi-Co Pc) series as cathode catalysts, a single chamber air cathode microbial fuel cell (SCMFC) was used to optimize the structure of Bi-Co PC. The aim of this paper is to solve the problem of poor performance and high cost of cathode catalyst for microbial fuel cell. The specific research results of this thesis are summarized as follows: (1) Bi-Co Pc/C is used as a new cathode catalyst instead of expensive Pt/C for microbial fuel cells, and the reaction conditions of this series of catalyst batteries are optimized, including the amount of catalyst, The optimum conditions, such as the concentration of sodium acetate, ionic strength, pH value, etc. When the amount of catalyst is 1 mg / cm ~ (-2), the concentration of sodium acetate is 2 g / L, the concentration of sodium chloride is 0.1 mg / L, and the concentration of sodium chloride is 0.1 mg / h, the structure optimization of microbial fuel cell is the best. The structure of Bi-Co Pc composite with N i O and COO on the surface of Bi-Co Pc is optimized. A binuclear cobalt phthalocyanine complex is formed. The synthesized Bi-Co Pc/C-Ni O and Bi-Co Pc/C-Co O catalysts were compared with cobalt based catalysts Co Pc/C and Bi-Co PC / C, oxide catalysts Ni O and Co O. The morphology and surface structure of the catalyst were characterized by TEM XPS. XPS results showed that Ni O and Co O could increase the content of oxygen and nitrogen functional groups in the catalyst. Cyclic voltammetry and linear sweep voltammetry show that the oxygen reduction peaks of Bi-Co Pc/C-Ni O and Bi-Co Pc/C-Co O are at -0.12 V and -0.22 V, respectively, which is better than that of Bi-Co Pc / C without recombination. The maximum power density of SCMFC using Bi-Co Pc/C-Ni O and Bi-Co Pc/C-Co O as cathode catalysts is 400 and 368 MW / m2, respectively, which is close to the maximum power density of 450m W / m2 of commercial Pt/C. The results show that the composite catalysts Bi-Co Pc/C-Ni O and Bi-Co Pc/C-Co O may be substituted. Commercial Pt/C catalyst. 3) the effect of calcination at high temperature on the structure and performance of Bi-Co PC catalyst was studied in detail. The calcination temperature is 300600800 cu. The morphology, surface composition and structure of the catalyst were characterized by SEMMOTEMX PSX XRD. The electrocatalytic activity of the catalyst was measured by cyclic voltammetry and linear scanning voltammetry. The results show that Bi-Co Pc/C-800 exhibits the best catalytic activity for oxygen reduction at the calcination temperature of 800 鈩，

本文编号：1966451