Low-Pd FeCoNiCrCu High-Entropy Alloy Catalysts Encapsulated in N-Doped Carbon Nanofibers for Enhanced Nitroarene Hydrogenation

High-entropy alloys (HEAs), composed of multiple principal elements in near-equiatomic ratios, offer vast compositional tunability and synergistic electronic interactions for heterogeneous catalysis. Here, we report a nitrogen-doped carbon nanofiber (N–CNF) encapsulated HEA catalyst, Fe 26 Co 13 Ni 24 Cr 10 Cu 17 Pd 10 @N–CNFs, synthesized via electrospinning followed by controlled thermal treatment. The resulting ~16 nm HEA nanoparticles are uniformly embedded within a conductive N-doped carbon matrix, forming a robust core–shell architecture. Despite the low Pd loading (10 at%), the catalyst achieves 99% nitrobenzene conversion with >99% aniline selectivity at 60°C—an 8.9-fold activity enhancement over Pd@N–CNFs. Furthermore, it retains >95% conversion after five consecutive reaction cycles, underscoring its excellent structural and catalytic durability. The outstanding performance arises from Pd-induced electronic modulation within the entropy-stabilized multimetallic matrix and synergistic confinement by the N-doped carbon framework. This work establishes a cost-efficient and durable HEA-based platform for selective hydrogenation, offering new insights into entropy-driven electronic regulation in multimetallic catalysts.