Achieving efficient and robust catalytic reforming on dual-sites of Cu species

Abstract

Catalytic reforming provides a practical technique for on-board hydrogen production in fuel cell applications. The high energy density, easy transportation and non-toxicity of biomass-derived dimethyl ether (bio-DME) offer potential to replace methanol for on-board steam reforming (SR). Presently, the reaction mechanism over conventional Cu-based SR catalysts remains elusive, limiting the rational design of highly efficient reforming systems. Herein, we build a catalytic system for bio-DME SR with dual-sites of Cu species, i.e., Cu⁺ and Cu⁰ sites, and achieve a record-high H₂ production rate of 1145 mol kg_cat⁻¹ h⁻¹. Via regulating the ratios of the dual-sites of Cu, we clearly describe molecular understandings on SR. And we discover that the substantially boosted activity is induced by a new Cu⁺-determined reaction path substituting the conventional Cu⁰-determined path. Intrinsically, Cu₂O can act as a physical spacer and hydroxyl consumer to suppress the aggregation of metallic Cu species in SR. Due to the unique structure of metallic Cu surrounded by Cu₂O, the catalyst exhibits robust catalytic performance even after severe thermal treatment. These findings open a new avenue for designing efficient catalytic reforming systems with commercial potential.