Breaking Activity-Stability Trade-Off by Switching Reaction Pathway for Efficient Electrosynthesis of Glycerate at Industrial-Scale Current Density

Abstract

The selective electrooxidation of biomass represents a sustainable solution for the synthesis of high-valued chemicals, yet it remains challenging to balance activity, selectivity, and stability. Herein, we report the selective regulation of β-NiCoOOH and γ-NiCoOOH through the precise modulation of precursors, demonstrating β-NiCoOOH as active catalyst exhibit excellent performance for the electrocatalytic valorization of glycerol to glycerate (GLA) with a remarkable selectivity of 78.44% and an industrial-scale current density of 1 A cm⁻² in an anion exchange membrane electrolyzer for continuous long-term operation of 1080 h. We revealed that the electrooxidation of glycerol to C3 product is contingent on the generation of β-NiCoOOH phase with Co³⁺ species as the dominant active center while γ-NiCoOOH phase with a large amount of Co⁴⁺ sites is beneficial to the cleavage of C─C bond for C1 product. Mass spectrometry and density functional theory (DFT) calculations elucidate that β-NiCoOOH featuring inert lattice oxygen modulates the electronic configuration of the key glyceraldehyde intermediate, which enhances the stability of C─C bond, suppresses undesired cleavage, and thereby promotes the selective electrosynthesis of GLA via the ∙OH-assisted adsorbate evolution mechanism (AEM). This work provides a scalable strategy and offers deep insights into the phase-dependent reaction mechanisms in electrocatalytic biomass upgrading.