In this study, iron carbide (Fe₃C) particles were encapsulated in graphitic carbon shells by a facile carbonation process. These core-shell carbides, in which iron carbide is encapsulated in graphene-like layer (Fe₃C@C) and nitrogen doped graphene-like layer (Fe₃C@C–N) were investigated as oxygen evolution reaction (OER) catalysts to investigate the effect of the carbon shell on catalyst activity and stability. Due to the protective effect of the graphitic carbon shells, the performance of Fe₃C@C and Fe₃C@C–N were considerably better than the bare Fe₃C nanoparticles. The OER activity of Fe₃C@C–N is comparable with that of carbon-supported ruthenium oxide (RuO₂/C), and this core-shell carbide has a remarkable stability and high turnover frequency under alkaline conditions. To elucidate the real active sites of these core-shell carbides, the role of the Fe₃C core, Fe–N_x active sites, and effect of nitrogen doping in the shell were investigated in detail.

在这项研究中，碳化铁（Fe ₃ C）颗粒通过一种容易的碳化过程被封装在石墨碳壳中。研究了这些核-壳碳化物，其中氧化铁被包裹在石墨烯样层（Fe ₃ C @ C）和氮掺杂石墨烯样层（Fe ₃ C @ C–N）中，作为氧释放反应（OER）催化剂研究碳壳对催化剂活性和稳定性的影响。由于石墨碳壳的保护作用，Fe ₃ C @ C和Fe ₃ C @ C–N的性能明显优于裸露的Fe ₃ C纳米颗粒。Fe ₃的OER活性C @ C–N可与碳载钌氧化物（RuO ₂ / C）相媲美，并且这种核壳型碳化物在碱性条件下具有显着的稳定性和高周转率。为了阐明这些核-壳碳化物的真实活性位，详细研究了Fe ₃ C核的作用，Fe–N _x活性位以及壳中氮掺杂的影响。