Li Jin-Cheng, Qin Xueping, Xiao Fei, Liang Caihong, Xu Mingjie, Meng Yu, Sarnello Erik, Fang Lingzhe, Li Tao, Ding Shichao, Lyu Zhaoyuan, Zhu Shangqian, Pan Xiaoqing, Hou Peng-Xiang, Liu Chang, Lin Yuehe, Shao Minhua
Fok Ying Tung Research Institute, Hong Kong University of Science and Technology, Guangzhou 511458, China.
School of Mechanical and Materials Engineering, Washington State University, Pullman, Washington 99164, United States.
Nano Lett. 2021 May 26;21(10):4508-4515. doi: 10.1021/acs.nanolett.1c01493. Epub 2021 May 17.
Highly efficient noble-metal-free electrocatalysts for oxygen reduction reaction (ORR) are essential to reduce the costs of fuel cells and metal-air batteries. Herein, a single-atom Ce-N-C catalyst, constructed of atomically dispersed Ce anchored on N-doped porous carbon nanowires, is proposed to boost the ORR. This catalyst has a high Ce content of 8.55 wt % and a high activity with ORR half-wave potentials of 0.88 V in alkaline media and 0.75 V in acidic electrolytes, which are comparable to widely studied Fe-N-C catalysts. A Zn-air battery based on this material shows excellent performance and durability. Density functional theory calculations reveal that atomically dispersed Ce with adsorbed hydroxyl species (OH) can significantly reduce the energy barrier of the rate-determining step resulting in an improved ORR activity.
用于氧还原反应（ORR）的高效无贵金属电催化剂对于降低燃料电池和金属空气电池的成本至关重要。在此，提出了一种由锚定在氮掺杂多孔碳纳米线上的原子分散铈构建的单原子Ce-N-C催化剂，以促进氧还原反应。该催化剂具有8.55 wt%的高铈含量，在碱性介质中氧还原反应半波电位为0.88 V，在酸性电解质中为0.75 V，具有高活性，与广泛研究的Fe-N-C催化剂相当。基于这种材料的锌空气电池表现出优异的性能和耐久性。密度泛函理论计算表明，吸附有羟基物种（OH）的原子分散铈可以显著降低速率决定步骤的能垒，从而提高氧还原反应活性。
