Abstract:

In proton exchange membrane fuel cell (PEMFC), for the sake of cost and practicality, the oxygen required for oxygen reduction reaction is basically from air. However, the pollutants in the air, such as SO₂ and NO₂, will lead to the poisoning of Pt catalyst. Therefore, improving the anti-toxicity of the catalyst has become one of the key issues to promote the large-scale application of PEMFC. The research progresses in the development of anti-toxicity catalysts for oxygen reduction reaction (ORR) and the anti-toxicity mechanism were introduced in this paper. At present, many ORR catalysts has been developed, mainly including platinum-based catalysts, non-noble metal catalysts and carbon-based catalysts. Their anti-toxicity could be improved mainly by inhibiting the electronic interaction between poisonous substance and catalyst, enhancing the spillover effects, reducing the oxidation potential of poisonous substance, introducing heteroatom (such as nitrogen, phosphorus), etc. At the same time, it is faced with some problems, such as the decrease of catalyst conductivity and activity and the complex preparation procedure. How to develop a catalyst with good anti-toxicity while maintaining its activity and stability has become a key research direction.

Key words: fuel cells, electrocatalyst, anti-toxicity, oxygen reduction reaction

摘要：

在质子交换膜燃料电池（proton exchange membrane fuel cell，PEMFC）中，出于成本和实用性等方面的考虑，氧还原反应所需氧气基本都来自于空气。而空气中存在的污染物，如SO₂、NO₂等都会导致阴极Pt催化剂中毒。因此，提高催化剂的抗毒性就成为推动PEMFC规模化实际应用的关键问题之一。本文介绍了PEMFC氧还原催化剂抗毒性的研究进展，并分析其抗中毒机理。目前，抗毒性阴极催化剂已取得一定的突破，其主要可分为铂基改性催化剂、非贵金属催化剂和非金属碳基催化剂，通过抑制毒化物与铂之间的电子作用、增强溢出效应、锚定金属原子、引入杂原子（如氮、磷）、采用不易中毒的金属等方式可增强催化剂的抗毒性。与此同时，抗毒性催化剂也面临一定的问题，如催化剂导电性下降、活性降低、制备复杂等。如何在保持催化剂活性和稳定性的同时，开发出具有良好抗毒性的催化剂已成为研究人员的重点研究方向。

关键词: 燃料电池, 催化剂, 抗毒性, 氧还原