• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>Conference in Series with Tutorial, Exhibition and Application Market;European pefc and electrolyser forum >Composition-Stability Relations for Non-Noble Metal Catalysts for Polymer Electrolyte Fuel Cell Cathodes
【24h】

Composition-Stability Relations for Non-Noble Metal Catalysts for Polymer Electrolyte Fuel Cell Cathodes

机译：用于聚合物电解质燃料电池阴极非贵金属催化剂的组成 - 稳定性关系

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Polymer electrolyte fuel cell (PEFC) commercialization would be significantly enhanced if the Pt-based catalysts needed to catalyze the oxygen reduction reaction (ORR) at the cell’s cathode were substituted with inexpensive materials based on abundant metals. Such non-noble metal catalysts (NNMCs) have been studied since the 1960s, and the ongoing refinement of their syntheses has recently led to ORR-activities and high-current performances commensurate with those of Pt-catalysts. However, these qualities are accompanied by a poorly understood, fast deactivation that ultimately prevents NNMCs’ device implementation. In order to shed light on the relative impact of the different mechanisms discussed in the literature (e.g., radical attack, demetallation) on the overall instability and their likely relation with the materials’ composition, there is an urgent need to develop synthesis strategies allowing for a fine control of the catalyst’s speciation. With this motivation, we have developed a novel NNMC-preparation approach in which an inexpensive precursor and polyacrylonitrile are used as the porous template and C-/ N-precursor, respectively, and a complex of Fe~(2+) with 1,10-phenanthroline acts as the metal source. The initial mixing of all precursors is followed by heat treatment and acid washing, along with a second heat treatment that improves the catalyst’s ORR-activity (assessed by rotating disc electrode voltammetry). Tuning of the synthesis parameters (e.g., precursors’ ratios, heat treatment temperature) results in catalysts with different (micro-)porous-and N-contents, unveiling the importance of these variables on the corresponding ORR-activity. Finally, polymer electrolyte fuel cell tests unveil that the most active NNMC displays a promising, initial ORR-activity (≈ 10 AgNNMC-1 at 0.8 V) that promptly decays during a potentiostatic test at 0.5 V – a behavior that is tentatively assigned to the flooding of the excessively-microporous NNMC catalyst layer.
机译：如果在细胞阴极上催化氧还原反应（ORR）所需的Pt基催化剂被基于丰富的金属被廉价的材料被廉价的材料取代，则聚合物电解质燃料电池（PEFC）商业化将得到显着提高。自20世纪60年代以来已经研究了这种非贵金属催化剂（NNMC），并且它们合成的正在进行的改进最近导致ORR-活性，并且与PT催化剂的高电流性能相称。然而，这些品质伴随着众所周知的快速停用，最终能够防止NNMCS设备实现。为了阐明在文献中讨论的不同机制的相对影响（例如，激进攻击，缺失）对整体不稳定性和它们与材料的组成的可能性关系，迫切需要开发允许的合成策略对催化剂的形态进行精细控制。通过这种动机，我们开发了一种新的NNMC制备方法，其中廉价的前体和聚丙烯腈分别用作多孔模板和C-/ N-前体，以及1,10的Fe〜（2+）的复合物-phenanthroLine充当金属来源。所有前体的初始混合之后是热处理和酸洗，以及改善催化剂的orr活性的第二热处理（通过旋转盘电极伏安法评估）。合成参数调整（例如，前体比，热处理温度）导致具有不同（微级）多孔和N-含量的催化剂，揭示这些变量对相应的ORR活性的重要性。最后，聚合物电解质燃料电池测试推出，最活跃的NNMC显示出有希望的初始ORR-活性（≈10AgNMC-1，0.8V），其在0.5V的稳定性试验期间迅速衰减 - 暂时分配给的行为淹没过度微孔的NNMC催化剂层。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号