过渡金属氧化物氧还原催化剂的研究进展

doi:10.13208/j.electrochem.180147

摘要/Abstract

摘要： 过渡金属氧化物（TMOs）是阴离子交换膜燃料电池最有前途的氧还原催化剂之一. 目前，TMOs的氧还原活性同铂基催化剂相比仍然有一定的差距，研究如何合成具有高催化活性的TMOs催化剂非常重要. 导电性和本征活性一直被认为是开发高性能TMOs催化剂的两个关键因素，本文着重总结与评述了近年来有关TMOs氧还原催化剂在导电性和本征活性方面的研究进展，尝试提出了未来提高TMOs氧还原催化活性的努力方向.

关键词: 过渡金属氧化物, 氧还原反应, 燃料电池

Abstract: Transition metal oxides (TMOs) based catalysts have become the most promising catalysts to be employed in anion exchange membrane fuel cell for the sluggish oxygen reduction reaction (ORR). However, their ORR activity is still far from that of the Pt-based catalysts. Therefore, it is important to develop high performance TMO based catalysts. Electrical conductivity and intrinsic activity have been regarded as the two keys to affect the ORR activity of the TMOs based catalysts. In this review, we focused on the recent progresses in the fundamental viewpoints on the electrical conductivity and intrinsic activity of the TMOs based ORR catalysts. Accordingly, the strategies to enhance the electrical conductivity and intrinsic activity are also summarized. The electrical conductivity could be reinforced in two ways. On the one hand, by coupling with the conductive materials, the external electrical conductivity of TMOs based catalysts could be elevated strongly. On the other hand, the intrinsic electrical conductivity of TMOs based catalysts could be enhanced by introducing oxygen vacancies or doping other cations or anions into TMOs. For the intrinsic activity of the TMOs based ORR catalysts, the crystal structure modulation for TMOs based catalysts is presented. Besides, the ORR descriptor of TMOs based catalysts, which is important for the future catalysts design, is also concluded in this review. And the conclusions and some future perspectives are also outlined. Although many strategies have been proposed to evaluate the electrical conductivity of TMOs based catalysts, there is still room for the further enhancement when the durability of TMOs based catalysts has been taken into consideration. And the ORR mechanism of TMOs based catalysts also should be further explored. Hence, there is a challenging but desired avenue for the development of the high performance TMOs based catalysts which are expected to be applied into anion exchange membrane fuel cell.

Key words: transition-metal-oxides, oxygen reduction reaction, fuel cell

中图分类号:

O646

王尧，魏子栋. 过渡金属氧化物氧还原催化剂的研究进展[J]. 电化学（中英文）, 2018, 24(5): 427-443.

WANG Yao, WEI Zi-dong. Recent Process in Transition-Metal-Oxide Based Catalysts for Oxygen Reduction Reaction[J]. Journal of Electrochemistry, 2018, 24(5): 427-443.

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