Efficient electrocatalytic oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid with Fe-Ni3S2@NiFe-PBA nanocubes.

• The Fe-Ni 3 S 2 @NiFe-PBA/NF electrocatalyst is synthesized by a two-step method. • Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst can convert 100 % of HMF and achieve 97.1 % FDCA yield. • Doping of Fe facilitates the deprotonation of Ni2+-OH forming the active Ni3+-O. • The Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst shows robust stability after 10 cycles in HMFOR. The electrooxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA) represents a promising avenue for generating value-added products derived from biomass. Nevertheless, the development of highly efficient electrocatalysts for HMF electrooxidation (HMFOR) remains an ongoing challenge. In this study, we present a novel approach wherein Fe-doped Ni 3 S 2 @NiFe-PBA nanocubes are synthesized directly on three-dimensional nickel foam (NF) substrates using a straightforward hydrothermal reaction and subsequent impregnation. This composite Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst showcases exceptional performance in HMFOR (a faraday efficiency of 97.4 %), characterized by both its remarkable conversion (100 %) and impressive FDCA yield (97.1 %), coupled with its robust stability over ten cycles. The heightened HMFOR activity exhibited by the Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst can be contributed to the introduction of Fe into the Ni 3 S 2 matrix. This deliberate doping strategy engenders accelerated charge transfer kinetics, an increased abundance of accessible surface-active sites, and improved conductivity, thereby enhancing the overall HMFOR performance. By establishing these outcomes, this investigation lays a foundation for the prospective design of electrocatalysts with applications in biomass utilization and energy conversion. In this work, we synthesize Fe-Ni 3 S 2 @NiFe-PBA nanocubes on a Ni foam using a hydrothermal reaction and subsequent impregnation process. The introduction of Fe3+ into the Ni 3 S 2 matrix can increase the Ni3+/Ni2+ ratio, accelerated charge transfer kinetics, an increased abundance of accessible surface active sites, and improved conductivity, collectively enhancing the overall HMFOR performance. As a result, the Fe-Ni 3 S 2 @NiFe-PBA/NF catalyst demonstrates the ability to convert 100 % of HMF at fixed 1.46 V vs RHE and achieve 97.1 % yield in FDCA generation, which is a 37 % higher than that of Ni 3 S 2 /NF. [Display omitted] [ABSTRACT FROM AUTHOR]