Highly Efficient Electrooxidation of 5-Hydroxymethylfurfural by NiCuP Supported on Porous Laser-induced Graphene

The electrooxidation of 5-hydroxymethylfurfural (HMF) has emerged as a promising way to generate high-value-added bio-based products. However, improving catalyst selectivity for HMF and inhibiting competitive oxygen evolution reaction (OER) in a limited potential range remain long-term targets. In this work, the self-supported LIG-NiCuP electrode, utilizing porous laser-induced graphene (LIG) skeleton as the substrate and loaded with NiCuP compound, is designed for the efficient and highly selective electrooxidation of HMF to 2,5-furandicarboxylic acid (FDCA). The surface reconstruction of electrode forms a LIG-NiCuP/NiCu(OH)x heterostructure, demonstrating high activity (HMF conversion 99.7%, FDCA yield 92.6%) for HMF oxidation reaction (HMFOR). Studies indicate that the low activity of Cu for OER allows it to function as a co-catalyst, enhancing the selectivity of Ni-based primary catalyst for HMF. In addition, the pine needle-like structure of Cu can optimize the morphology of catalyst deposited on LIG skeleton, increasing the contact area with HMF. On the other hand, in terms of the substrate to support metal catalysts,  LIG fabrication combines the characteristics of rapidity, simplicity, scalability, and low cost, therefore, holding high promise in practical applications. Overall, the material system and processing method in this work present a significant step toward developing efficient catalyst electrodes for biomass conversion.