Wang Qichen, Lyu Lulu, Hu Xu, Fan Wenqi, Shang Chunyan, Huang Qirui, Li Zhipeng, Zhou Zhen, Kang Yong-Mook
Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics, Northwestern Polytechnical University, Xi'an 710072, P. R. China.
Department of Materials Science and Engineering, Korea University, Seoul 02841, Republic of Korea.
Angew Chem Int Ed Engl. 2025 Apr 7;64(15):e202422920. doi: 10.1002/anie.202422920. Epub 2025 Mar 12.
The catalytic activities of the Fe-N-C single-atom catalysts (SACs) are associated with the varying atomic interactions through its characteristic coordination geometry. Yet, modulation of the surface curvature of carbon acting as a supporting body has not been investigated. Herein, we report the superior catalytic activity for the oxygen reduction reaction (ORR) and enhanced performance for urea oxidation reaction (UOR) of single Fe atoms anchored on a highly curved N-doped carbon dodecahedron with concave morphology (Fe SA/NhcC). Theoretical calculations and in situ spectroscopy disclose that the curvature of the carbon support helps to shorten the bond length of Fe-N, spatially redistributing the charges around the Fe and thereby lowering the d-band center toward optimal adsorption for oxygenated species. The Fe SA/NhcC catalyst displays an ultrahigh half-wave potential of 0.926 V for ORR and a small potential difference of 0.686 V for bifunctional ORR/UOR. A rechargeable Zn-urea-air battery with the Fe SA/NhcC cathode displays robust discharge durability, excellent cycling lifespan and higher energy efficiency compared to conventional Zn-air batteries. This work provides new insight into promoting the catalytic activity of SACs through varying the surface curvature of the supporting carbon, tailoring geometric configuration and electronic states of SACs.
铁氮碳单原子催化剂（SACs）的催化活性与其通过特征配位几何结构产生的不同原子相互作用相关。然而，作为载体的碳的表面曲率调制尚未得到研究。在此，我们报道了锚定在具有凹面形态的高度弯曲的氮掺杂碳十二面体（Fe SA/NhcC）上的单个铁原子对氧还原反应（ORR）具有优异的催化活性以及对尿素氧化反应（UOR）具有增强的性能。理论计算和原位光谱表明，碳载体的曲率有助于缩短Fe-N的键长，在空间上重新分布Fe周围的电荷，从而将d带中心降低至对含氧物种的最佳吸附。Fe SA/NhcC催化剂对ORR显示出0.926 V的超高半波电位，对双功能ORR/UOR显示出0.686 V的小电位差。与传统锌空气电池相比，具有Fe SA/NhcC阴极的可充电锌尿素空气电池显示出强大的放电耐久性、优异的循环寿命和更高的能量效率。这项工作为通过改变载体碳的表面曲率、调整SACs的几何构型和电子态来促进SACs的催化活性提供了新的见解。
