Topological iron silicide with H* intermediate modulated surface for efficient electrocatalytic hydrogenation of nitrobenzene in neutral medium.

Noble-metal free topological FeSi electrocatalyst is controllably designed using a solvent-free microwave method for efficient electrocatalytic hydrogenation of nitrobenzene. Benefiting the high surface coverage of active H* intermediates, FeSi achieves nitrobenzene conversion of 99.7% and aniline yield of 93.8% in neutral medium, which are superior to previous candidates and FeSi synthesized via the traditional arc-melting method under same conditions. [Display omitted] Electrocatalytic hydrogenation of nitrobenzene (Ph-NO 2) reaction (EHNR) has been considered as a potential alternative to the traditional thermocatalytic process in the production of high-value aniline (Ph-NH 2). However, due to the absence of robust catalyst and low surface H* coverage, the EHNR faces the challenges of undesired performance and indetermined mechanism. Herein, we construct a type of noble-metal free topological FeSi (M-FeSi) materials through a solvent-free microwave strategy for efficient EHNR in neutral medium. Impressively, benefiting from abundant active H* intermediates on the surface of M-FeSi catalyst, the topological M-FeSi catalyst exhibits 99.7% conversion of Ph-NO 2 and 93.8% yield of Ph-NH 2 after 200 C in neutral medium, which are superior to previous candidates and FeSi catalyst synthesized via the traditional arc-melting method under same conditions. Besides, theoretical calculations validate that high surface H* coverage over M-FeSi catalyst is conducive to switching the rate-determining step from Ph-NO 2 * → Ph-NO* to Ph-NO* → Ph-NHOH*, and thus decreasing the total energy barrier of electrocatalytic Ph-NH 2 production. [ABSTRACT FROM AUTHOR]