From Zn-N-C to Fe-N-C: Active-Site Imprinting As a New Method for the Synthesis of Highly Active PGM-Free Catalysts for PEMFC

催化作用 质子交换膜燃料电池 过渡金属 材料科学 活动站点 化学工程 高定向热解石墨 化学 无机化学 组合化学 纳米技术 有机化学 石墨 工程类
作者
Davide Menga,Iztok Arčon,Yansheng Li,F. E. Wagner,Burak Koyutürk,Francisco Ruiz‐Zepeda,Miran Gaberšček,Hubert A. Gasteiger,Tim Patrick Fellinger
出处
期刊:Meeting abstracts 卷期号:MA2020-02 (36): 2271-2271
标识
DOI:10.1149/ma2020-02362271mtgabs
摘要

The high cost and the restricted availability of Platinum-Group-Metals (PGM) used in current catalysts is one of the major hurdles for the large-scale commercialization of Proton Exchange Membrane Fuel Cells (PEMFCs). In the last decade, great efforts have been made to develop efficient PGM-free catalysts for the oxygen reduction reaction (ORR), especially metal-nitrogen-doped carbons (M-N-Cs, with M = Fe, Co). The activity gap towards Pt has successfully been narrowed, now reaching the activity requirements for practical applications. 1-3 For this class of catalysts, the active site is a MN 4 moiety, as known from molecules such as phthalocyanines and porphyrins. 4 Due to the metastability of the MN 4 sites at the temperature of their pyrolytic formation, the final transition metal loading is currently limited and significant amounts of inorganic byproducts are formed. Although synthesis protocols have been successfully optimized, multiple processing steps are required, making the preparation time-consuming. In this contribution we will show that Zn 2+ ions can be utilized in our novel concept of active-site imprinting, where Zn is used as template-ion in a pyrolytic process to form Zn-N-C precursor materials. 5 The Zn-N-C materials presented in this work are nitrogen-doped carbons comprising ZnN 4 sites, obtained with high yield and from inexpensive precursors. The active-site imprinted carbon supports possess high surface area and hierarchical porosity, which makes them structurally advantageous for catalytic applications in terms of mass transport and high accessibility of the active sites. Through a zinc-to-iron ion exchange reaction, Fe-N-C catalysts with high Fe loading are obtained at only 170 °C. Since the active-site formation by the Zn-to-Fe exchange reaction can be conducted at low temperatures, the structural properties of the Zn-N-C precursor material are retained. 6 Moreover, this synthetic procedure assures the absence of the otherwise obtained harmful side-phases (e.g., iron carbide). Cryo-Mössbauer and X-ray adsorption spectroscopy, supported by calculations of the extended X-ray absorption fine structure, reveal an exclusive presence of Fe as single atoms coordinated to four nitrogen atoms, i.e., in form of the desired FeN 4 moieties. Identical-location scanning transmission electron microscopy with atomic resolution is further employed to visualize the trans-metalation event. The herein obtained catalysts match the state-of-the-art electrocatalytic activity for Fe-N-C catalyts, both in a rotating disk electrode and in single cell PEMFC measurements. The novel synthesis method will be discussed regarding its advantages and disadvantages compared to the conventional pyrolytic M-N-C catalyst syntheses, with a focus on the potential to surpass the current limitations of restricted active-site density and catalyst stability. ACKNOWLEDGEMENTS: The German Federal Ministry of Economic Affairs and Energy (BMWi) is acknowledged for funding within the Verbundproject innoKA (Project No.: 03ET6096A) REFERENCES: M. Lefèvre, E. Proietti, F. Jaouen and J.-P. Dodelet, Science , 2009, 324 , 71-74. R. Bashyam and P. Zelenay, Nature , 2006, 443 , 63-66. H. A. Gasteiger, S. S. Kocha, B. Sompalli and F. T. Wagner, Applied Catalysis B , 2005, 56 , 9-35. Q. Jia, N. Ramaswamy, U. Tylus, K. Strickland, J. Li, A. Serov, K. Artyushkova, P. Atanassov, J. Anibal, C. Gumeci, S. C. Barton, M.-T. Sougrati, F. Jaouen, B. Halevi and S. Mukerjee, Nano Energy , 2016, 29 , 65-82. A. Mehmood, J. Pampel, G. Ali, H. Y. Ha, F. Ruiz-Zepeda and T.-P. Fellinger, Advanced Energy Materials , 2018, 8 . D. Menga, F. Ruiz-Zepeda, L. Moriau, M. Šala, F. Wagner, B. Koyutürk, M. Bele, U. Petek, N. Hodnik, M. Gaberšček and T.-P. Fellinger, Advanced Energy Materials , 2019, 9 , 1902412. Figure 1

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
共享精神应助Volcano采纳,获得10
2秒前
2秒前
2秒前
ali完成签到,获得积分20
3秒前
han发布了新的文献求助10
4秒前
大个应助无限雨南采纳,获得10
5秒前
丘比特应助幽默尔蓝采纳,获得10
5秒前
EED发布了新的文献求助10
6秒前
6秒前
yy完成签到,获得积分10
7秒前
7秒前
7秒前
李爱国应助十三儿采纳,获得10
8秒前
ali发布了新的文献求助10
9秒前
9秒前
HOME发布了新的文献求助10
11秒前
熊大哥发布了新的文献求助10
13秒前
14秒前
科研马完成签到,获得积分10
15秒前
猫和老鼠发布了新的文献求助10
16秒前
16秒前
17秒前
发篇Sci不过分吧完成签到,获得积分20
17秒前
奥特超曼应助易槐采纳,获得10
19秒前
19秒前
上官若男应助Supreme采纳,获得10
19秒前
熊大哥完成签到,获得积分10
19秒前
19秒前
20秒前
小蘑菇应助威武的手链采纳,获得10
20秒前
可爱千兰完成签到,获得积分10
20秒前
十三儿完成签到,获得积分20
20秒前
21秒前
21秒前
木木发布了新的文献求助20
21秒前
重要鑫磊完成签到,获得积分10
23秒前
23秒前
ccc发布了新的文献求助10
24秒前
24秒前
24秒前
高分求助中
A new approach to the extrapolation of accelerated life test data 1000
ACSM’s Guidelines for Exercise Testing and Prescription, 12th edition 500
‘Unruly’ Children: Historical Fieldnotes and Learning Morality in a Taiwan Village (New Departures in Anthropology) 400
Indomethacinのヒトにおける経皮吸収 400
Phylogenetic study of the order Polydesmida (Myriapoda: Diplopoda) 370
基于可调谐半导体激光吸收光谱技术泄漏气体检测系统的研究 350
Robot-supported joining of reinforcement textiles with one-sided sewing heads 320
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 3988920
求助须知:如何正确求助?哪些是违规求助? 3531290
关于积分的说明 11253247
捐赠科研通 3269903
什么是DOI,文献DOI怎么找? 1804830
邀请新用户注册赠送积分活动 882027
科研通“疑难数据库(出版商)”最低求助积分说明 809052