Acta Chimica Sinica ›› 2020, Vol. 78 ›› Issue (4): 355-362.DOI: 10.6023/A20010017 Previous Articles    

Special Issue: 多孔材料:金属有机框架(MOF)


界面增强的CeO2/FeNi MOF高效析氧催化剂

代迷迷a,b,c,d, 王健b, 李麟阁b, 王琪a,b, 刘美男b,e, 张跃钢a,b,d,f   

  1. a 上海科技大学 物质科学与技术学院 上海 201210;
    b 中国科学院 苏州纳米技术与纳米仿生研究所 苏州 215123;
    c 中国科学院 上海硅酸盐研究所 上海 200050;
    d 中国科学院大学 北京 100049;
    e 苏州纳米技术与纳米仿生研究所南昌研究院 南昌 330000;
    f 清华大学 物理系 北京 100084
  • 投稿日期:2020-01-16 发布日期:2020-04-07
  • 通讯作者: 刘美男, 张跃钢;
  • 基金资助:

High-performance Oxygen Evolution Catalyst Enabled by Interfacial Effect between CeO2 and FeNi Metal-organic Framework

Dai Mimia,b,c,d, Wang Jianb, Li Lingeb, Wang Qia,b, Liu Meinanb,e, Zhang Yueganga,b,d,f   

  1. a School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China;
    b Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China;
    c Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China;
    d University of Chinese Academy of Sciences, Beijing 100049, China;
    e Division of Nanomaterials and Jiangxi Key Lab of Carbonene Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Nanchang 330000, China;
    f Department of Physics, Tsinghua University, Beijing 100084, China
  • Received:2020-01-16 Published:2020-04-07
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Nos. 21433013, 21303129), Outstanding Youth Fund of Jiangxi Province (No. 20192BCB23028) and the Science and Technology Project of Jiangxi Province (No. 20192BCD40017).

Oxygen evolution reaction (OER) is a crucial half reaction of electrochemical water splitting and metal-air batteries. But its sluggish four-electron reaction leads to a high overpotential. Current commercial OER catalysts are mainly noble metal-based materials, but their high cost restricts their broad application. Therefore, extensive efforts have been devoted to exploring low-cost and efficient OER catalysts. Nonprecious metal-based materials have been regarded as promising OER catalyst candidates, due to their abundancy on the earth, controllable morphologies and tunable chemical states. Among various nonprecious metal-based materials, metal-organic frameworks (MOFs) have attracted much attention, because of their large specific surface area and rich metal centers. However, their poor electrochemical activities, stabilities and conductivities severely affect their application in OER catalysis. To improve the activities of MOFs, several methods have been adopted, such as synthesizing ultrathin nanosheets, growing MOFs on nickel foam or carbon cloth, doping heteroatoms, and introducing synergistic interactions between two materials. In 1970, Wagner proposed a space-charge theory, which indicates that the carrier property can be tuned through adjusting interface. Inspired by this theory, constructing metal oxide-catalyst interface seems to be a promising strategy to improve activities of catalysts. CeO2 is a well-known cocatalyst due to its reversible Ce3+/Ce4+ redox. Previous works have demonstrated that OER performance can be effectively improved through introducing CeO2 since it can speed up the electron mobility and induce strong interaction between CeO2 and metal sites. In this work, an efficient OER catalyst was achieved through introducing CeO2 into FeNi MOF catalyst. FeNi MOF nanosheet arrays grown on nickel foam was firstly prepared via a solvothermal process. Then CeO2 nanoclusters (5 nm) were coated onto FeNi MOF surface by electrodeposition. A series of characterizations were employed to study the morphology, structure and surface electronic state information of the as-obtained CeO2/FeNi MOF. From X-ray photoelectron spectroscopic analysis, the doping of CeO2 clusters and the strong electronic interaction between CeO2 clusters and FeNi MOF induce the formation of Fe/Ni-O-Ce bonds and optimize the electronic structures of Fe/Ni sites, which will enhance OER activities. The OER performance tests confirm that CeO2/FeNi MOF indeed exhibits a superior OER activity than FeNi MOF alone. The hybrid catalyst delivers a higher mass activity (235.4 A·g-1) and a faster turnover frequency (0.065 s-1) than those of FeNi MOF (43.8 A·g-1, 0.018 s-1). Compared with FeNi MOF, CeO2/FeNi MOF also shows better OER kinetics, as evidenced by a decreased Tafel slope, a reduced charge transfer resistance. Besides, CeO2/FeNi MOF presents an outstanding stability (50 h, 50 mA·cm-2). All these features make our CeO2/FeNi MOF a potential catalyst in the future application. The interfacial strategy through introducing CeO2 to modulate Fe and Ni active sites may open a door for developing high-performance OER catalysts in future.

Key words: MOF, CeO2, interfacial effect, catalyst, oxygen evolution reaction