Rational Design of a Bi-Pd Based Intermetallic Alloy as a Promising Electrocatalyst for Oxidation of 5-Hydroxymethylfurfural (HMF) to 2,5-Furandicarboxylic Acid (FDCA)

The transformation of biomass-based substances into valuable products through the application of electric energy at room temperature is essential for promoting a circular economy. In this study, 5-hydroxymethylfurfural (HMF) has been effectively oxidized into 2,5-furandicarboxylic acid (FDCA) via an electrochemical process in 1 M KOH electrolyte. However, the intermetallic alloy-based materials show promising electrocatalytic performances, owing to their tunable electrical properties and ordered geometric arrangement of atoms. In this context, the Bi-Pd based intermetallic alloy Bi2Pd5 has been synthesized by a facile one-step electrodeposition method on 3D nickel foam. The deposited electrocatalyst (Bi2Pd5) showed a homogeneous deposition and hierarchical morphology. Bi2Pd5 electrocatalyst has successfully achieved the electrocatalytic oxidation of HMF to FDCA; however, FDCA is an essential precursor for the sustainable synthesis of polymers (like polyethylene furanoate). The reaction intermediates and products have been measured using high-performance liquid chromatography (HPLC), 1H NMR, 13C NMR, and liquid chromatography-mass spectrometry (LC-MS), which led to a 96% yield of FDCA and a complete conversion (∼100%) of HMF in just 9 h. The reaction kinetics and potential routes were further examined. In addition, the catalyst’s reusability was examined for five catalytic cycles. This study, as the first to use Bi-Pd-based catalysts for HMFOR (5-hydroxymethylfurfural electro-oxidation reaction), offers a promising outlook for energy conversion and electrocatalytic processing of biomass-derived monomers.