催化学报 ›› 2022, Vol. 43 ›› Issue (7): 1710-1718.DOI: 10.1016/S1872-2067(21)63960-8

• 二氧化碳催化转化专栏 • 上一篇    下一篇

镍高度分散在铁基钙钛矿用于高温固体氧化物电解池阴极的CO2电催化还原研究

周莹杰a,b, 刘天夫b, 宋月锋b, 吕厚甫b, 刘清雪b,c, 塔娜b, 张小敏b,#(), 汪国雄b,*()   

  1. a东华大学材料科学与工程学院, 纤维材料改性国家重点实验室, 上海201620
    b中国科学院大连化学物理研究所, 催化基础国家重点实验室, 中国科学院纳米科学卓越创新中心, 洁净能源国家实验室, 辽宁大连116023
    c中国科学院大学, 北京100049
  • 收稿日期:2021-08-31 接受日期:2021-10-09 出版日期:2022-07-18 发布日期:2022-05-20
  • 通讯作者: 张小敏,汪国雄
  • 基金资助:
    国家自然科学基金(22072146);国家自然科学基金(22005045);中国科学院洁净能源创新研究院合作基金(DNL201923);中央高校业务基金(2232020D-07);东华大学青年教师科研启动经费.

Highly dispersed nickel species on iron-based perovskite for CO2 electrolysis in solid oxide electrolysis cell

Yingjie Zhoua,b, Tianfu Liub, Yuefeng Songb, Houfu Lvb, Qingxue Liub,c, Na Tab, Xiaomin Zhangb,#(), Guoxiong Wangb,*()   

  1. aState Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
    bState Key Laboratory of Catalysis, CAS Center for Excellence in Nanoscience, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China
    cUniversity of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2021-08-31 Accepted:2021-10-09 Online:2022-07-18 Published:2022-05-20
  • Contact: Xiaomin Zhang, Guoxiong Wang
  • About author:Guoxiong Wang (Dalian Institute of Chemical Physics, Chinese Academy of Science) was invited as a young member of the 5th and 6th Editorial Board of Chin. J. Catal. Prof. Guoxiong Wang received his B.A. degree from Wuhan University (China) in 2000, and Ph.D. degree from Dalian Institute of Chemical Physics, Chinese Academy of Sciences in 2006. He carried out postdoctoral research Catalysis Research Center in Hokkaido University (Japan) from 2007 to 2010. Since the end of 2010, he has been working in State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. He is Distinguished Young Scholars Recipients of National Natural Science Foundation of China (2021) and outstanding member of youth innovation promotion association of Chinese Academy of Sciences (2019). His research interests mainly focus on electrocatalysis, especially electrochemical conversion of CO2, CO and CH4. He has published more than 120 peer-reviewed papers.
  • Supported by:
    National Natural Science Foundation of China(22072146);National Natural Science Foundation of China(22005045);DNL Cooperation Fund, CAS(DNL201923);Fundamental Research Funds for the Central Universities(2232020D-07);Initial Research Funds for Young Teachers of Donghua University.

摘要:

利用太阳能、风能等可再生清洁电能将CO2催化转化为高附加值化学品或燃料, 在CO2转化和可再生电能存储方面表现出极具潜力的应用前景. 高温固体氧化物电解池(SOEC)可将CO2电催化还原为CO, 具有能量效率高、成本低等优点. 目前, 钙钛矿氧化物已被广泛应用于SOEC电解CO2的阴极材料, 但存在电极催化活性低等问题, 因而限制其规模化发展和应用. 通常采用浸渍、原位溶出或掺杂等策略引入大量活性中心以提升钙钛矿氧化物电极性能. 然而, 这些策略仍然面临一些挑战, 如浸渍法易引入大颗粒物种而堵塞气体传输通道, 原位溶出法能耗较大且析出量较少, 掺杂法调控活性幅度有限. 因此, 发展新型简便方法以合理构建具有高度分散活性位点的阴极材料, 可有效拓展电化学三相反应界面, 进而加快SOEC高温电解CO2的电极动力学速率.

本文采用机械研磨法将1.0% NiO高度分散于La0.8Sr0.2FeO3-δ-Ce0.8Sm0.2O2-δ(Ni-LSF-SDC)表面, 用作SOEC阴极材料进行CO2电解. 扫描电子显微镜(SEM)、透射电子显微镜、扫描透射电子显微镜(STEM)和X射线衍射等结构表征表明, 低载量的Ni物种高度分散在LSF-SDC表面, 并不会堵塞载体的多孔网络结构, 且与钙钛矿镧锶铁(LSF)具有更好的亲和性. X射线光电子能谱和程序升温脱附结果表明, 高度分散的Ni物种改善了LSF-SDC的电子结构, 不仅提升了体系中电子对的含量, 还在体系中形成大量氧空位, 显著提升了荷质传递效率. 当Ni-LSF-SDC作为SOEC阴极时, 在800 °C, 1.6 V时, CO2电解电流密度最高达到1.53 A·cm-2, 比未经过Ni修饰的LSF-SDC阴极提高了约91%. 同时Ni-LSF-SDC阴极表现出较高的稳定性, 在800 °C和1.2 V下稳定运行66 h后有微弱的性能衰减, 电流衰减率为0.85  mA·cm-2·h-1. 对稳定性测试后电解池的电极涂覆层截面进行SEM和STEM表征, 结果表明, 电极表面有少量极小的NiO颗粒形成, 且集流体涂覆层的Au元素长时间运行后可迁移到电极内部, 这些是导致电解池电解效率衰减的主要因素.

总之, 本文通过采用一种简便的方法制备出低载量高度分散的Ni修饰铁基钙钛矿阴极材料, 高度分散的Ni物种可以调控钙钛矿氧化物载体的电子结构和氧空位浓度, 显著提高了SOEC电解CO2性能. 本文为合理设计和优化SOEC阴极CO2电催化材料的结构以提升其电催化性能提供了新思路.

关键词: CO2电解, 固体氧化物电解池, 钙钛矿氧化物, 镍物种

Abstract:

Feasible construction of cathode materials with highly dispersed active sites can extend the triple-phase boundaries, and therefore leading to enhanced electrode kinetics for CO2 electrolysis in solid oxide electrolysis cell (SOEC). Herein, highly dispersed nickel species with low loading (1.0 wt%) were trapped within the La0.8Sr0.2FeO3-δ-Ce0.8Sm0.2O2-δ via a facial mechanical milling approach, which demonstrated excellent CO2 electrolysis performance. The highly dispersed nickel species can significantly alter the electronic structures of the LSF-SDC without affecting its porous network and facilitate oxygen vacancy formation, thus greatly promote the CO2 electrolysis performance. The highest current density of 1.53 A·cm-2 could be achieved when operated under 800 °C at 1.6 V, which is about 91% higher than the LSF-SDC counterpart.

Key words: CO2 electrolysis, Solid oxide electrolysis cells, Perovskite oxide, Nickel species