A unified electrocatalytic platform for the chemicals-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 maintaining a high Faradaic efficiency of ~94.9%. Comprehensive characterizations 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 over-oxidation and carbon backbone degradation. A membrane electrode assembly (MEA) electrolyzer towards 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.