直接甲酸燃料电池阳极电催化剂中碳载体材料的研究

发布时间：2018-01-08 02:12

  本文关键词：直接甲酸燃料电池阳极电催化剂中碳载体材料的研究　出处：《燕山大学》2014年硕士论文　论文类型：学位论文

  更多相关文章： 直接甲酸燃料电池 电氧化 钯纳米粒子 催化剂 碳载体材料

【摘要】：直接甲酸燃料电池作为一种清洁高效的能量转换装置，由于其相对于直接甲醇燃料电池的快速氧化动力学、低毒性、低Nafion膜透过率而受到越来越多的关注。然而，阳极催化剂的低催化活性、低稳定性、易失活和载体易腐蚀仍然限制着直接甲酸燃料电池的实际应用。 本文主要研究了几种常用碳材料作为催化剂载体时对钯基催化剂催化甲酸电氧化的性能影响，发现了多壁碳纳米管作为载体材料时具有较高的催化活性和稳定性。由于钯和碳材料之间的强相互作用，碳材料的添加对于钯催化剂的新型活性位点的形成起着至关重要的作用。结果表明碳材料在催化剂中不仅仅起着载体的作用，而且参与了甲酸电氧化过程中钯基催化剂的新型活性位点的形成，该发现对于研究Pd/C催化剂催化甲酸电氧化的反应机理、寻找合适的载体材料起着至关重要的作用。 同时，本文也系统研究了氮掺杂乙炔碳黑对甲酸电氧化反应的影响。通过在氮气流中不同温度下热解乙炔碳黑和三聚氰胺得到氮掺杂的乙炔碳黑，并将该材料负载钯纳米粒子用作甲酸电氧化的催化剂。发现当热处理温度为900℃时，所对应的催化剂Pd/N-C-900具有最大的催化活性、稳定性和耐一氧化碳中毒性能。在0.5mol·L-1H2SO4和0.5mol·L-1HCOOH的混合溶液中，Pd/N-C-900催化剂的催化活性是普通Pd/C催化剂和商业Pd/C催化剂的2.84倍和0.96倍。同时研究了甲酸浓度和温度效应对Pd/N-C催化剂的影响，结果表明氮掺杂的确可以提高甲酸电氧化的性能。发现氮掺杂提高甲酸电氧化性能的原因是改善的钯纳米粒子的分散和修饰的电子效应，，结果表明Pd/N-C催化剂在直接甲酸燃料电池中作为一种高性能催化剂具有广阔的应用前景。
[Abstract]:As a clean and efficient energy conversion device, direct formic acid fuel cell (DFC) is less toxic than direct methanol fuel cell (DMFC) because of its rapid oxidation kinetics. Low Nafion membrane transmittance has attracted more and more attention. However, the anode catalyst has low catalytic activity and low stability. Deactivation and carrier corrosion still limit the practical application of direct formic acid fuel cells. In this paper, the effect of several common carbon materials on the electrooxidation of formic acid over palladium based catalysts was studied. It was found that multi-walled carbon nanotubes had high catalytic activity and stability when they were used as carrier materials because of the strong interaction between palladium and carbon materials. The addition of carbon materials plays an important role in the formation of new active sites of palladium catalysts. The results show that carbon materials not only act as carriers in the catalysts. It is also involved in the formation of new active sites of palladium based catalysts in the process of formic acid electrooxidation. This discovery is useful for the study of the reaction mechanism of Pd/C catalysts for formic acid electrooxidation. Finding suitable carrier materials plays an important role. At the same time, the effect of nitrogen-doped acetylene black on the electrooxidation of formic acid was studied systematically. The nitrogen-doped acetylene black was obtained by pyrolysis of acetylene carbon black and melamine at different temperatures in nitrogen flow. The palladium nanoparticles were used as catalysts for the electrooxidation of formic acid. It was found that the corresponding catalyst Pd/N-C-900 had the highest catalytic activity when the heat treatment temperature was 900 鈩

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