Selective Electrocatalytic Hydrogenation of Nitroarenes and Ketones Enabled by Proton Conductive Graphene Oxide Membrane Reactor

Electrocatalytic hydrogenation offers a sustainable alternative to conventional thermocatalytic methods, which typically requires high temperature and pressure, and toxic additives. Herein, we report a proton-conductive graphene oxide (GO) membrane reactor that enables selective and additive-free electrocatalytic hydrogenation of nitroarenes and ketones under ambient conditions. The GO membrane, dual functionalized with imidazole and cerium ions, exhibits enhanced proton conductivity (0.160 mS cm−1) and near ideal proton selectivity (t = 0.956) along with improved structural stability in aqueous and mixed solvent environments. Integrated into a two-compartment electrochemical system utilizing molecular hydrogen as the sole reductant, the membrane reactor achieves up to 93% yield with excellent chemoselectivity. Mechanistic investigations indicate an azobenzene-mediated pathway during nitroarene reduction. Compared to conventional proton exchange membrane systems, the developed membrane eliminates the need for supporting electrolytes while maintaining efficient proton transport. This work demonstrates a robust and scalable platform for green electrosynthesis and highlights the potential of functionalized GO membranes in advanced catalytic applications.