Abstract:

Direct methanol fuel cells (DMFCs) are energy conversion devices that directly use liquid methanol as fuel and convert the chemical energy of methanol into electrical energy. They have significant advantages, such as high energy conversion efficiency, low cost, and convenient storage and transportation. In this paper, based on the mechanism of electrocatalytic methanol oxidation reaction (MOR), the research progress of electrocatalytic MOR over Pt single crystal and Pt-based alloy catalysts is systematically reviewed. The influence of structure and properties of Pt-based catalysts on its electrochemical performance is summarized. Typical preparation methods of Pt-based electrocatalysts are described. It is found that the intermediate species CO_ads produced during the methanol oxidation process have high adsorption energy and reaction activation energy on the surface of Pt active sites, which leads to a decrease in the overall performance of the Pt catalysts. In addition, the possible electrocatalytic oxidation paths of methanol are analyzed. The idea of improving CO_ads poisoned Pt catalysts by regulating the methanol dehydrogenation step is proposed, which provides necessary theoretical support for optimizing the microstructure of Pt-based catalysts and analyzing the microscopic mechanism of MOR, and laies a theoretical foundation for promoting the large-scale application of DMFCs.

Key words: fuel cells, methanol oxidation reaction, electrochemistry, catalysts

摘要：

直接甲醇燃料电池（DMFCs）是一种直接以液态甲醇为燃料，将甲醇的化学能转换成电能的能量转化装置，具有能量转化效率高、成本低、储运方便等显著优势。本文基于电催化甲醇氧化反应（MOR）机理，系统综述了Pt单晶和Pt基合金催化剂电催化MOR的研究进展，重点总结了Pt基催化剂结构及性质对其电化学性能的影响机制，阐述了三种Pt基电催化剂的典型制备方法，发现MOR中间物种CO_ads在Pt活性位表面具有较高的吸附能和反应活化能，从而导致Pt催化剂整体性能下降。此外，分析了可能的甲醇电催化氧化路径，提出通过调控甲醇脱氢步骤改善CO_ads毒化Pt催化剂的思路，为优化设计Pt基催化剂的微观结构和解析MOR微观机理提供一定的理论支撑，为助推DMFCs大规模应用奠定理论基础。

关键词: 燃料电池, 甲醇氧化反应, 电化学, 催化剂