Effect of the nature of catalysts on kinetics and mechanisms of electrocatalytical reactions:

开发新材料的必要性是加拿大对燃料电池和电池以及电解槽应用的高能量转换效率的不断要求。因此，了解许多基本和关键的电催化反应的基本原理仍然是一个重要的问题。 在所研究的各种系统中，O2和CO2还原以及NH3和短链醇氧化具有特别的技术兴趣。 最重要的特征是用于电化学反应的材料的效率。本论文的主要研究方向是在合金、改性表面和良好定义的表面上，对这些氧化还原过程的动力学和机理进行研究，以阐明和理解电催化过程中的电化学现象（吸附现象、电沉积和成核）。 电极反应的动力学将与基底的表面结构和性质相关。利用我们定制的电化学质谱系统（DEMS）配备薄层流动池（与质谱仪连接），催化剂表面状态和性质将被选择性地修饰，以研究其在反应中间体和产物分布中的作用。这种技术，它给出了分子特异性，允许反应产物被跟踪，在线，同时与电位和时间。从技术上讲，这项研究旨在更好地了解电催化剂，并最终导致改进的电催化剂用于能源转换和环境应用。

The necessity for the development of new materials is the unceasing requirement for high energy conversion efficiencies for fuel cells and batteries and electrolyser applications in Canada. For this reason, an understanding of the fundamentals of many basic and crucial electrocatalytical reactions remains an important issue.    Of various systems examined, O2  and CO2 reduction as well as NH3 and short chain alcohol oxidation are of particular technological interest.  The most important characteristic is  the efficiency of the material used for the electrochemical reactions. Detrimental side reactions can occur, such as the poisoning effect caused by irreversible adsorption of products/intermediates of the electrochemical reactions.My research is focused on initiating a study of the kinetics and mechanisms of these redox processes at alloys, modified surfaces and well-defined surfaces for the elucidation and the understanding of the electrochemical phenomena involved in electrocatalytic processes (adsorption phenomena, electrodeposition and nucleation).   The kinetics of the electrode reactions will be correlated to the surface structure and nature of the substrate. Taking advantage of our custom made Electrochemical Mass Spectrometry system (DEMS) equipped with a  thin layer flow cell (interfaced with the mass spectrometer),  the catalyst surface state and nature will be modified selectively to study its role in the distribution of the reaction intermediates and products. This technique, which gives molecular specificity, permits the reaction products to be followed, on-line, concurrently with potential and time. Technologically, this research aims towards a better understanding of electrocatalysts and, ultimately, should lead to improved electrocatalysts for energy conversion and environmental applications.