Alkalization of acetylacetonates: A facile and versatile method to prepare Ni-based hydroxides for the electrochemical production of bio-based 2,5-furandicarboxylic acid

A facile and versatile synthesis method is required for the preparation of Ni-based hydroxides, which are efficient electrocatalysts for oxidation of 5-hydroxymethylfurfural (HMF) to high-value added chemical 2,5-furandicarboxylic acid (FDCA). Herein, a preparation strategy for Ni-based hydroxides is provided based on the alkalization of acetylacetonates. With carbon black as the support, ultrathin porous Ni(OH)2 nanosheets (∼1 nm in thickness) are obtained with HMF conversion and FDCA yield reaching ∼100% and 98.1%, respectively. With carbon felt or nickel foam as the substrate, the self-supporting Ni(OH)2 electrode can continuously operate in anion exchange membrane electrolyzer for up to 80 h with the content of FDCA in product between 80% and 100%. After the scale-up of preparation process, the performance of catalyst and electrode is maintained. Moreover, Ni-Co bimetallic hydroxide can be also prepared by this method, which presents enhanced activity for HMF oxidation at low electrode potentials.