Efficient Electrocatalytic Upgradation of Furan-Based Biomass: Key Roles of a Two-Dimensional Mesoporous Poly(m‑phenylenediamine)-Graphene Heterostructure and a Ternary Electrolyte

The development of electrocatalytic systems for efficient biomass conversion under mild conditions and understanding their mechanisms are of profound significance but remain challenging. Here, we report the development of a two-dimensional polymer-based mesoporous electrocatalyst (meso-PA/PmPD/GO) for biomass conversion, which comprises phytic acid (PA)-doped mesoporous poly­(m-phenylenediamine) layers coated on graphene oxide. Meanwhile, a ternary electrolyte containing 1-butyl-3-methylimidazolium tetrafluoroborate (BmimBF4), acetonitrile, and H2O is selected. The combination of meso-PA/PmPD/GO and the electrolyte realizes efficient conversion of two important biomass derivatives. One involves the oxidation of furfuryl alcohol to 6-hydroxy-2,3-dihydro-6H-pyrano-3-one with high faradic efficiency (FE: 82.2%) and selectivity (86.1%). The other involves the oxidation of furfural to 5-hydroxy-2­(5H)-furanone with record-high FE (98.2%) and selectivity (93.1%). A mechanistic study unveils that N-heterocyclic carbenes (Bmim*) generated from BmimBF4 act as the reaction-determining species. The synergistic effect of the PA doping and mesoporous polymeric structure in meso-PA/PmPD/GO favors mass transport and electron–hole separation/transfer to the reactants, thus boosting catalytic performance.