CeO2 nano-nail-induced interface electronic effects boost ethanol oxidation

Abstract

Developing ethanol oxidation reaction (EOR) electrocatalysts for direct ethanol fuel cells (DEFCs) with high catalytic activity, durability, and resistance to CO poisoning remains a major challenge. Herein, we synthesize a Pt/nCeO₂@NPC catalyst, consisting of Pt nanoparticles supported on a hybrid support of CeO₂ nano-nails (nCeO₂) and N-doped porous carbon (NPC). The unique nCeO₂ efficiently forms and adjusts the Pt–CeO₂ interface, modulating the electronic structure of the Pt nanoparticles. This electronic modulation yields an efficient and poison-resistant electrocatalyst for the ethanol oxidation reaction (EOR), thereby significantly enhancing the EOR catalytic activity of the catalyst. As a result, the optimized catalyst (Pt/nCeO₂@NPC) demonstrates a mass activity of 1374 mA mg_Pt⁻¹ in ethanol oxidation, which is 3.87 times higher than that of commercial Pt/C (355 mA mg_Pt⁻¹). Additionally, it maintains 72% and 48% of its initial activity after 500 and 2000 CV cycles, respectively, and shows a 20 mV negative shift in onset potential compared to that of Pt/NPC, indicating excellent durability and enhanced tolerance to CO poisoning. Meanwhile, combined experimental and theoretical analyses reveal that the strong electronic interaction between Pt-based nanoparticles and nCeO₂ modulates CO adsorption strength and supplies OH species to facilitate CO removal, thereby significantly enhancing the CO tolerance of the catalyst. This study thus proposes an innovative strategy for the design of highly efficient catalysts for DEFCs and advances the development of clean and sustainable energy technologies.