A unified electrocatalytic platform for the chemical–H2–electricity triad from biomass via interfacial electronic engineering

Abstract

The selective electrooxidation of biomass-derived 1,3-propanediol (1,3-PDO) to high-value 3-hydroxypropionic acid (3-HP) offers a sustainable route for chemical synthesis but is severely hindered by competitive C–C bond cleavage and sluggish reaction kinetics. Here, we propose an electronic structure tuning strategy through interfacial engineering, constructing a Pd–Ni(OH)₂ heterostructure to enhance the catalytic performance of Pd nanoparticles. The resulting catalyst exhibits exceptional activity toward the 1,3-PDO oxidation reaction (POR) in alkaline media, requiring a low potential of only 0.645 V (vs. RHE) to achieve a current density of 100 mA cm⁻² while retaining a high faradaic efficiency of ∼94.9%. Comprehensive characterization and density functional theory (DFT) calculations reveal that strong interfacial interaction induces a downshift in the d-band center of Pd. This electronic restructuring optimizes the adsorption energetics of key intermediates, facilitating rapid desorption of 3-HP from active Pd sites and thereby suppressing overoxidation and carbon backbone degradation. A membrane electrode assembly (MEA) electrolyzer towards the POR demonstrates robust stability, retaining faradaic efficiencies above 90% during continuous operation. Furthermore, we demonstrate an integrated synthesis–energy device by coupling the POR workflow with the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). This hybrid system, powered by the multifunctional Pd–Ni(OH)₂ catalyst, enables flexible temporal deployment via a mode-switching scheme between daytime (HER‖POR) and nighttime (ORR‖POR). Collectively, this work elucidates an effective strategy for selective biomass valorization through electronic structure tailoring, offering an appealing multidimensional solution for sustainable electrochemical synthesis.