Reverse Hydrogen Spillover at M/Cu Interfaces Drives Efficient Bipolar Hydrogen Production From Furfural...

Bipolar hydrogen production systems have attracted considerable interest for their low energy consumption and high efficiency. Understanding catalytic mechanisms and designing advanced electrocatalysts are central challenges in this field. In this work, we combine density functional theory (DFT) calculations with interface engineering to construct heterogeneous M/Cu interfaces (M = noble metals) for enhancing the furfural oxidation reaction in a bipolar hydrogen production system (FFOR-H₂), which integrates both non-faradaic and faradaic processes. Among the tested catalysts, Au/Cu heterojunction significantly promotes C─H bond cleavage via catalytic dehydrogenation in the non-faradaic step. Notably, this study reports the first example of reverse hydrogen spillover using organic compounds as hydrogen sources. During the faradaic process, the Au/Cu interface also delivers exceptional performance in the FFOR-H₂ system, achieving high activity (0.05 V vs RHE at 10 mA cm^-2), 92.7% furfural conversion, and nearly 100% Faradaic efficiency for both product streams. This work offers valuable insights into harnessing hydrogen spillover and interfacial catalysis to advance bipolar hydrogen production, presenting an economical and sustainable route beyond conventional energy conversion systems.