Mechanism and kinetics of electrocatalytic reactions

电催化反应机理和动力学

• 批准号: 691-2007
• 负责人: Lasia, Andrzej
• 金额: $ 4.37万
• 依托单位: Université de Sherbrooke
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=365544
• 关键词: Mechanism; kinetics; electrocatalytic; reactions

The purpose of the proposed research is to study electrocatalytic reactions of hydrogen adsorption, absorption and evolution, mechanism and kinetics of metal hydride formation, and modeling of porous electrodes. This study will lead to a better understanding of these reactions and to develop better electrode materials for hydrogen storage and water electrolysis. This research includes:1. Mechanism and kinetics of hydrogen absorption: Our earlier studies suggest that the direct absorption mechanism is the main reaction path and that going through adsorbed hydrogen is much slower. This process will be further studied on other Pt alloys as Pd-Rh, Pd-Ru, etc., which are very important from the electrocatalytic point of view. Adsorption of H and the influence of different poisons on the H absorption processes will be studied. Adsorption isotherms and the kinetics of hydrogen adsorption and absorption will be determined. It should be stressed that several poisons of hydrogen adsorption act as promoters of hydrogen absorption increasing the kinetics of this process. These processes, studied initially in the presence of sulfuric acid will be extended to the non adsorbed perchloric acid and to alkaline solutions.2. Kinetics and thermodynamics of adsorption processes: Hydrogen adsorption reaction is the simplest electrocatalytic reaction. Its kinetics already studied in our laboratory on polycrystalline Pt will be further studied on other noble metals (polycrystalline Rh, Ru, Ir), alloys (Pd-Rh, Pd-Ru, Pd-Ir) and monocrystalline metals using the twin electrode technique developed recently in our lab.3. Modeling of porous electrodes: The kinetics of simple redox reactions will be studied on porous electrodes characterized by the well defined porous geometry (e.g. brush electrodes) to test the theory.

本研究的目的是研究氢的吸附、吸收和析出的电催化反应，金属氢化物形成的机理和动力学，以及多孔电极的建模。这项研究将导致更好地了解这些反应，并开发更好的电极材料用于储氢和水电解。本研究包括：1.吸氢机理和动力学：我们早期的研究表明，直接吸收机理是主要的反应途径，而通过吸附的氢要慢得多。这一过程将在Pd-Rh、Pd-Ru等其他铂合金上进一步研究，这从电催化的观点来看是非常重要的。H的吸附和不同毒物对H吸收过程的影响将被研究。吸附等温线和氢吸附和吸收的动力学将被确定。应该强调的是，氢吸附的几种毒物作为氢吸附的促进剂，增加了该过程的动力学。这些过程，最初研究在硫酸的存在下，将扩展到非吸附高氯酸和碱性溶液。2.吸附过程的动力学和热力学：氢吸附反应是最简单的电催化反应。我们实验室已经在多晶Pt上研究了其动力学，将使用我们实验室最近开发的双电极技术在其他贵金属（多晶Rh、Ru、Ir）、合金（Pd-Rh、Pd-Ru、Pd-Ir）和单晶金属上进一步研究。3.多孔电极的建模：简单的氧化还原反应的动力学将在多孔电极上进行研究，其特征在于良好定义的多孔几何形状（例如刷电极），以测试理论。