Wang Sidi, He Qun, Wang Changda, Jiang Hongliang, Wu Chuanqiang, Chen Shuangming, Zhang Guobin, Song Li
National Synchrotron Radiation Laboratory, CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China.
Small. 2018 May;14(19):e1800128. doi: 10.1002/smll.201800128. Epub 2018 Apr 10.
Developing efficient and low-cost defective carbon-based catalysts for the oxygen reduction reaction (ORR) is essential to metal-air batteries and fuel cells. Active sites engineering toward these catalysts is highly desirable but challenging to realize boosted catalytic performance. Herein, a sandwich-like confinement route to achieve the controllable regulation of active sites for carbon-based catalysts is reported. In particular, three distinct catalysts including metal-free N-doped carbon (NC), single Co atoms dispersed NC (Co-N-C), and Co nanoparticles-contained Co-N-C (Co/Co-N-C) are controllably realized and clearly identified by synchrotron radiation-based X-ray spectroscopy. Electrochemical measurements suggest that the Co/Co-N-C catalyst delivers optimized ORR performance due to the rich Co-N active sites and their synergistic effect with metallic Co nanoparticles. This work provides deep insight for rationally designing efficient ORR catalyst based on active sites engineering.
开发用于氧还原反应（ORR）的高效且低成本的缺陷型碳基催化剂对于金属空气电池和燃料电池至关重要。对这些催化剂进行活性位点工程设计非常必要，但要实现催化性能的提升却具有挑战性。在此，报道了一种用于实现碳基催化剂活性位点可控调节的三明治状限域途径。具体而言，通过基于同步辐射的X射线光谱法可控制备并清晰鉴定出三种不同的催化剂，包括无金属氮掺杂碳（NC）、单钴原子分散的NC（Co-N-C）以及含钴纳米颗粒的Co-N-C（Co/Co-N-C）。电化学测量表明，由于丰富的Co-N活性位点及其与金属钴纳米颗粒的协同效应，Co/Co-N-C催化剂具有优化的ORR性能。这项工作为基于活性位点工程合理设计高效ORR催化剂提供了深刻见解。
