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
哈哈完成签到,获得积分10
1秒前
淡定访琴完成签到,获得积分10
3秒前
大力云朵完成签到,获得积分10
5秒前
ADcal完成签到 ,获得积分10
5秒前
5秒前
tony完成签到,获得积分10
5秒前
苏苏完成签到,获得积分10
7秒前
WuFen完成签到 ,获得积分10
8秒前
淘宝叮咚完成签到,获得积分10
8秒前
高高从云完成签到 ,获得积分10
9秒前
情怀应助唐唐采纳,获得10
10秒前
科研肥料完成签到,获得积分10
11秒前
每天都在找完成签到,获得积分10
11秒前
桐桐应助zzw采纳,获得20
11秒前
11秒前
吕布完成签到,获得积分10
12秒前
12秒前
ChenYifei完成签到,获得积分10
16秒前
qq发布了新的文献求助10
16秒前
Smiley完成签到 ,获得积分10
19秒前
hzauhzau完成签到 ,获得积分10
19秒前
白桃完成签到 ,获得积分10
21秒前
小八统治世界完成签到 ,获得积分10
22秒前
Lotus完成签到,获得积分10
22秒前
btyyl完成签到,获得积分10
23秒前
屈岂愈发布了新的文献求助10
24秒前
25秒前
HH发布了新的文献求助10
26秒前
葵葵完成签到,获得积分10
27秒前
高大莺完成签到 ,获得积分10
29秒前
zzw发布了新的文献求助20
30秒前
幸福果汁完成签到,获得积分10
31秒前
量子星尘发布了新的文献求助10
31秒前
谢谢谢谢谢谢谢谢完成签到 ,获得积分10
32秒前
Akim应助biofresh采纳,获得30
32秒前
长安发布了新的文献求助10
33秒前
34秒前
zzw完成签到,获得积分10
39秒前
Guochunbao完成签到,获得积分10
40秒前
哈哈哈完成签到 ,获得积分10
42秒前
高分求助中
【提示信息,请勿应助】关于scihub 10000
Les Mantodea de Guyane: Insecta, Polyneoptera [The Mantids of French Guiana] 3000
徐淮辽南地区新元古代叠层石及生物地层 3000
The Mother of All Tableaux: Order, Equivalence, and Geometry in the Large-scale Structure of Optimality Theory 3000
Handbook of Industrial Diamonds.Vol2 1100
Global Eyelash Assessment scale (GEA) 1000
Picture Books with Same-sex Parented Families: Unintentional Censorship 550
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 4038184
求助须知:如何正确求助?哪些是违规求助? 3575908
关于积分的说明 11373872
捐赠科研通 3305715
什么是DOI,文献DOI怎么找? 1819255
邀请新用户注册赠送积分活动 892662
科研通“疑难数据库(出版商)”最低求助积分说明 815022