Lyu Shuai, Wang Li, Li Zhe, Yin Shukun, Chen Jie, Zhang Yuhua, Li Jinlin, Wang Ye
Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, South-Central University for Nationalities, Wuhan, 430074, China.
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.
Nat Commun. 2020 Dec 4;11(1):6219. doi: 10.1038/s41467-020-20068-5.
The development of efficient catalysts for Fischer-Tropsch (FT) synthesis, a core reaction in the utilization of non-petroleum carbon resources to supply energy and chemicals, has attracted much recent attention. ε-Iron carbide (ε-FeC) was proposed as the most active iron phase for FT synthesis, but this phase is generally unstable under realistic FT reaction conditions (> 523 K). Here, we succeed in stabilizing pure-phase ε-FeC nanocrystals by confining them into graphene layers and obtain an iron-time yield of 1258 μmol gs under realistic FT synthesis conditions, one order of magnitude higher than that of the conventional carbon-supported Fe catalyst. The ε-FeC@graphene catalyst is stable at least for 400 h under high-temperature conditions. Density functional theory (DFT) calculations reveal the feasible formation of ε-FeC by carburization of α-Fe precursor through interfacial interactions of ε-FeC@graphene. This work provides a promising strategy to design highly active and stable Fe-based FT catalysts.
费托（FT）合成是利用非石油碳资源供应能源和化学品的核心反应，开发高效的费托合成催化剂最近备受关注。ε-碳化铁（ε-FeC）被认为是费托合成中活性最高的铁相，但该相在实际的费托反应条件下（>523K）通常不稳定。在此，我们通过将纯相ε-FeC纳米晶体限制在石墨烯层中成功使其稳定，并在实际的费托合成条件下获得了1258μmol gs的铁时空产率，比传统的碳负载铁催化剂高一个数量级。ε-FeC@石墨烯催化剂在高温条件下至少稳定400小时。密度泛函理论（DFT）计算表明，通过ε-FeC@石墨烯的界面相互作用，α-Fe前驱体碳化可形成ε-FeC。这项工作为设计高活性和稳定的铁基费托催化剂提供了一种有前景的策略。
