Energy‐Efficient, Sustainable Cascade Glucose Electrooxidation into Glucaric Acid

Abstract

ABSTRACT Glucaric acid (GRA) is a critical platform chemical for manufacturing biodegradable materials. Selective glucose (GLU) electrooxidation into GRA provides a sustainable route for biomass valorization. However, conventional methods suffer from energy‐intensive processes due to excessive operational potential exceeding 1.2 V. Here we demonstrate an energy‐efficient tandem system that decouples GRA electrosynthesis into cascade GLU‐to‐gluconic acid (GNA) and GNA‐to‐GRA oxidation. When pairing an Au/C catalyst for selective aldehyde oxidation and an AuPt/C catalyst for hydroxyl oxidation, we achieve 91.8% Faradaic efficiency and nearly 100% conversion efficiency at 0.6 V RHE for GLU‐to‐GNA oxidation, and 81% Faradaic efficiency and 90% conversion efficiency at 0.55 V RHE for GNA‐to‐GRA oxidation. Chronoamperometry demonstrates ∼100% substrate conversion with a minor decrease in product selectivity, confirming the catalyst's excellent stability. Our tandem system improves the overall GLU‐to‐GRA energy efficiency from 13.8% for conventional one‐step route to 31.8%. When oxygen reduction is selected as paired reaction, our system not only enables efficient chemical electrosynthesis, but is also estimated to generate electricity of 1.24 × 10 5  kWh per kiloton GRA, outperforming traditional method with energy consumption of 4.31 × 10 5  kWh. Our work establishes a sustainable and economically viable pathway for biomass valorization, offering a blueprint for circular, carbon‐neutral chemical production.