Stoichiometry, hierarchical arrangement and kinetics of electrode reactions at novel multi-components electrocatalytic materials

新型多组分电催化材料电极反应的化学计量、分级排列和动力学

• 批准号: RGPIN-2019-05975
• 负责人: Mohamedi, Mohamed
• 金额: $ 1.75万
• 依托单位: Institut national de la recherche scientifique
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=738633
• 关键词: Stoichiometry; hierarchical; arrangement; kinetics; electrode

The depletion of fossil fuel reserves and serious environmental issues has created tremendous energy challenges. It is now undeniable that electrochemistry- the interchange of chemical and electrical energy- is about to play a major role in energy production. As a clean, sustainable energy technology, direct ethanol fuel cells (DEFCs) have emerged as highly promising low carbon power sources for vehicles and as alternatives to rechargeable batteries in portable electronic devices. Yet, the commercialization of DEFCs is hindered by their low anode catalyst activities and the production of partial oxidation byproducts. In addition, proton exchange membranes-DEFCs are considered too bulky and costly, and they can be damaged by high concentrations of ethanol, known as the ethanol crossover effect. Our long-term objective is to develop membraneless mixed-reactants DEFCs (novel technology) with efficiency higher than 60%. Over the next five years, the main objective of our work is to develop and gain insights in the synthesis-structure-catalytic activity relationships of novel nanostructured highly active and efficient multicomponent anode catalysts for the electrocatalytic oxidation of ethanol (Theme I). Efforts will be focused on the addition of co-catalysts to platinum. We will choose materials composed of abundant and inexpensive metal oxide materials combined with ultra-low amounts of platinum and rhodium. We expect to discover the optimal structural arrangements of the atoms of the three components in the surface and bulk of the final active catalyst to maximize activity and selectivity. We will also develop selective cathode catalyst that is electroactive towards oxygen reduction reaction while tolerant to high concentrations of ethanol (Theme II). Considering that the size of oxygen molecule is much smaller than that of ethanol, our idea is develop a superficial material layer through which oxygen molecules can easily diffuse and be reduced at the platinum beneath layer surface while ethanol molecules remain impeded at the surface of the superficial layer. Like this higher ethanol concentrations could be used and superior electrochemical performance would be achieved. The results of this proposal will address Canada's research priority in the development of advanced nanomaterials based electrochemical clean/green technologies to deal with increasingly critical energy and environmental challenges as well as climate change, while training highly qualified personnel to exploit these opportunities. As to the fundamental issues, these studies will assist in establishing firm correlations between interfacial structures, compositions, and understanding of mechanistic aspects of new classes of catalytic materials. In addition, this proposed research program will be important to commercial applications in Canada such as, consumers' portable electronics and transport, or to specific users for road safety fuel cell-based sensors for ethanol detection.

化石燃料储备的枯竭和严重的环境问题带来了巨大的能源挑战，不可否认的是，电化学（化学能和电能的交换）将在能源生产中发挥重要作用。直接乙醇燃料电池（DEFC）已成为极具前景的车辆低碳电源以及便携式电子设备中可充电电池的替代品，然而，DEFC的商业化因其低阳极催化剂活性和部分生产而受到阻碍。此外，质子交换膜 - DEFC 被认为体积太大且成本高昂，并且它们可能会被高浓度的乙醇损坏，这被称为乙醇交叉效应。我们的长期目标是开发无膜混合反应物 DEFC。未来五年，我们工作的主要目标是开发并深入了解新型纳米结构高活性和高效的合成-结构-催化活性关系。用于乙醇电催化氧化的多组分阳极催化剂（主题 I）将集中于在铂中添加助催化剂我们将选择由丰富且廉价的金属氧化物材料与超低含量的铂和铑组成的材料。我们期望发现最终活性催化剂表面和本体中三种组分原子的最佳结构排列，以最大限度地提高活性和选择性。对氧还原反应具有电活性，同时耐受高浓度乙醇的催化剂（主题二）考虑到氧分子的尺寸比乙醇小得多，我们的想法是开发一种表面材料层，氧分子可以很容易地扩散到其中。并在铂下层表面被还原，而乙醇分子在表面层表面仍然受到阻碍，这样可以使用更高的乙醇浓度，并且将实现优异的电化学性能，该提案的结果将解决加拿大的研究重点。发展先进的基于纳米材料的电化学清洁/绿色技术，以应对日益严峻的能源和环境挑战以及气候变化，同时培训高素质人才以利用这些机会。至于基本问题，这些研究将有助于在界面结构、此外，这项拟议的研究计划对于加拿大的商业应用（例如消费者的便携式电子产品和运输）或基于道路安全燃料电池的特定用户来说非常重要。乙醇传感器检测。