Efficient Electrocatalytic Oxidation of 5-Hydroxymethylfurfural Coupled with 4-Nitrophenol Hydrogenation in a Water System

Electrocatalytic conversion of biomass-derived 5-hydroxymethylfurfural (HMF) to value-added 2,5-furandicarboxylic acid (FDCA) is of great significance for sustainable chemical production. The key challenge is to establish an electrocatalytic system with a wide potential window, which can selectively oxidize HMF to FDCA without causing water oxidation. In this study, Cu foam decorated with Cu(OH)(2) (CF-Cu(OH)(2)) was successfully fabricated as an efficient catalyst, and CuOOH active species generated by electrochemistry were demonstrated as the main catalytic sites for HMF oxidation. As a result, the current density of CF-Cu(OH)(2) reached up to 198.2 mA/cm(2) (100 mM HMF, 1.0 M KOH, 0.8 V vs Ag/AgCl), and a high faradic efficiency close to 100% for FDCA production (yield: 98.7%) was realized. Moreover, we reveal the mechanism for the electro-oxidation of HMF to FDCA and further provide an insight into the oxidation pathway for HMF. A paired electrochemical system exhibits superior catalytic performance of synergetic reactions (HMF oxidation and 4-NP reduction). Therefore, this work proposes a strategy to simultaneously produce two types of value-added chemicals at both electrodes, which can be applied in other electrocatalytic systems for the green synthesis of organic compounds.

Automated summary

In this study, Cu foam decorated with Cu(OH)(2) was used as an efficient catalyst for the electrocatalytic conversion of HMF to FDCA. The CuOOH active species were identified as the main catalytic sites for HMF oxidation, and the oxidation pathway of HMF was revealed. A strategy of simultaneously producing two types of value-added chemicals at both electrodes was proposed.