黑龙江大学付宏刚团队报道了，利用氮化钨介导的电子调制解锁Pt的优异抗氢氧化和CO中毒性能。相关研究成果发表在2024年10月28日出版的国际学术期刊《美国化学会杂志》。

提高铂基催化剂在阳极氢氧化反应（HOR）中的活性和抗CO中毒性，对质子交换膜燃料电池的发展提出了重大挑战。

该文中，研究人员利用理论计算证明氮化钨（WN）可以复杂地调节Pt的电子结构。这种调节优化了氢吸附，显著提高了HOR活性，同时削弱了CO吸附，显著增强了对CO中毒的抵抗力。通过合理设计的预筛选，研究人员合成了一种高效的催化剂，其包含负载在小尺寸WN/还原石墨氧化物上的最小Pt含量（仅1.4 wt%）(Pt@WN/rGO）。

正如预期的那样，这种催化剂显示出3060 A gPt^-1的显著酸性HOR质量活性，大约是商用20 wt%Pt/C催化剂的11.8倍。令人印象深刻的是，即使在1000ppm的CO存在下，它也能保持高活性，保留率为98.2%，表明其具有出色的抗毒性。

同步辐射操作分析表明，WN在电化学反应过程中协调了Pt的电子态，优化了氢吸附/解吸动力学。与Pt/rGO相比，这导致Pt@WN/rGO上CO剥离的峰值电位更低，这表明WN减轻了CO的竞争性吸附，提高了Pt上氢吸附位点的可用性。

协同效应显著加速了HOR活性，提高了抗中毒效果。组装好的PEMFC对H₂/CO混合物中10至1000ppm的CO浓度表现出相当大的耐受性。

附：英文原文

Title: Unlocking Superior Hydrogen Oxidation and CO Poisoning Resistance on Pt Enabled by Tungsten Nitride-Mediated Electronic Modulation

Author: Bin Cai, Di Shen, Ying Xie, Haijing Yan, Yucheng Wang, Xiaodong Chen, Lei Wang, Honggang Fu

Issue&Volume: October 28, 2024

Abstract: Enhancing the activity and CO poisoning resistance of Pt-based catalysts for the anodic hydrogen oxidation reaction (HOR) poses a significant challenge in the development of proton exchange membrane fuel cells. Herein, we leverage theoretical calculations to demonstrate that tungsten nitride (WN) can intricately modulate the electronic structure of Pt. This modulation optimizes the hydrogen adsorption, significantly boosting HOR activity, and simultaneously weakens the CO adsorption, markedly improving resistance to CO poisoning. Through prescreening with rational design, we synthesized an efficient catalyst comprising a minimal Pt content (only 1.4 wt %) supported on the small-sized WN/reduced graphite oxide (Pt@WN/rGO). As anticipated, this catalyst showcases a remarkable acidic HOR mass activity of 3060 A gPt–1, which is approximately 11.8 times greater than that of the commercial 20 wt % Pt/C catalyst. Impressively, it maintains high activity with 98.2% retention even in the presence of 1000 ppm of CO, indicating exceptional poison resistance. Operando synchrotron radiation analyses reveal that WN harmonizes the electron state of Pt during electrochemical reactions, optimizing hydrogen adsorption/desorption dynamics. This leads to a lower peak potential of CO stripping on Pt@WN/rGO compared to that on Pt/rGO, suggesting that WN mitigates competitive CO adsorption and enhances the availability of hydrogen adsorption sites on Pt. The synergistic effect significantly accelerates HOR activity and increases antipoisoning efficacy. The assembled PEMFC demonstrates substantial tolerance to CO concentration from 10 to 1000 ppm in the H2/CO mixture.

DOI: 10.1021/jacs.4c12720

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c12720