Enhanced Adsorption Kinetics and Capacity of a Stable CeF 3 @Ni 3 N Heterostructure for Methanol Electro‐Reforming Coupled with Hydrogen Production

Abstract Alkaline methanol‐water electrolysis system is regarded as an appealing strategy for electro‐reforming methanol into formate and producing hydrogen with low energy‐consumption compared with alkaline water electrolysis. However, stability and selectivity under high current densities for practical application remain challenging. Herein, a CeF 3 @Ni 3 N nanosheets array anchored on carbon cloth (CeF 3 @Ni 3 N/CC) was fabricated. The gradual extrusion of F species from Ni(OH) 2 lattices can stabilize hierarchical structure and construct abundant heterostructure interfaces. Moreover, CeF 3 can modulate electron distribution of Ni 3 N, thus simultaneously enhancing the surface adsorption kinetics and capability of methanol and OH − , which is conducive to enhanced methanol oxidation reaction (MOR) activity and selectivity. Therefore, bifunctional CeF 3 @Ni 3 N/CC exhibits low potential of 1.43 V at 500 mA cm −2 , along with high stability over 72 h and high faradaic efficiency (FEs) in MOR, as well as an overpotential of 76 mV to achieve 50 mA cm −2 for hydrogen evolution reaction (HER). Furthermore, membrane‐free CeF 3 @Ni 3 N/CC||CeF 3 @Ni 3 N/CC cell for MOR||HER delivers high electrocatalytic activity, long‐term stability and FEs at high current density of 300 mA cm −2 . This study highlights the importance of optimizing surface adsorption behavior of active species, as well as rational design of highly efficient heterostructure electrocatalysts for methanol upgrading coupled with hydrogen production.