香港科技大学邵敏华团队报道了Fe-N-C提高负载型纳米铂燃料电池的稳定性。相关研究成果于2022年10月25日发表于国际顶尖学术期刊《美国化学会杂志》。

分散在炭黑上的铂基纳米颗粒耐久性差是长寿命聚合物电解质燃料电池应用面临的挑战。最近的研究表明，Fe和N共掺杂碳（Fe-N-C）可能比传统的高比表面积碳更好。

该文中，研究人员发现在酸性和碱性介质中，Pt/Fe-N-C在电位循环过程中的电化学表面积保持率远优于市售Pt/C。原位电感耦合等离子体质谱研究表明，循环过程中Pt/Fe-N-C的Pt溶解速率是Pt/C的3倍。密度泛函理论计算进一步表明，Fe–N–C衬底可以为Pt纳米颗粒提供强大而稳定的支撑，并通过调整电子结构减轻氧化物的形成。强的金属-基底相互作用，加上较低的金属溶解速率和高度稳定的载体，可能是Pt/Fe-N-C稳定性显著增强的原因。

该发现突出了碳载体选择对于实现燃料电池用更持久的铂基电催化剂的重要性。

附：英文原文

Title: Fe–N–C Boosts the Stability of Supported Platinum Nanoparticles for Fuel Cells

Author: Fei Xiao, Yian Wang, Gui-Liang Xu, Fei Yang, Shangqian Zhu, Cheng-Jun Sun, Yingdan Cui, Zhiwen Xu, Qinglan Zhao, Juhee Jang, Xiaoyi Qiu, Ershuai Liu, Walter S. Drisdell, Zidong Wei, Meng Gu, Khalil Amine, Minhua Shao

Issue&Volume: October 25, 2022

Abstract: The poor durability of Pt-based nanoparticles dispersed on carbon black is the challenge for the application of long-life polymer electrolyte fuel cells. Recent work suggests that Fe- and N-codoped carbon (Fe–N–C) might be a better support than conventional high-surface-area carbon. In this work, we find that the electrochemical surface area retention of Pt/Fe–N–C is much better than that of commercial Pt/C during potential cycling in both acidic and basic media. In situ inductively coupled plasma mass spectrometry studies indicate that the Pt dissolution rate of Pt/Fe–N–C is 3 times smaller than that of Pt/C during cycling. Density functional theory calculations further illustrate that the Fe–N–C substrate can provide strong and stable support to the Pt nanoparticles and alleviate the oxide formation by adjusting the electronic structure. The strong metal–substrate interaction, together with a lower metal dissolution rate and highly stable support, may be the reason for the significantly enhanced stability of Pt/Fe–N–C. This finding highlights the importance of carbon support selection to achieve a more durable Pt-based electrocatalyst for fuel cells.

DOI: 10.1021/jacs.2c08305

Source: https://pubs.acs.org/doi/10.1021/jacs.2c08305