Electronic structure engineering of heterogeneous ceria-incorporated Pt/C as an efficient catalyst for boosting DMFCs performance

Abstract

The commercial development of direct methanol fuel cells (DMFCs) is hindered by the slow kinetics of both methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) for Pt-based electrocatalysts. Modulating the electronic configuration of Pt by a low-electronegativity second component can accelerate reaction kinetics. Herein, the heterogeneous PtCe-CeO2/C was designed by alloying Pt with ultra-low-electronegativity Ce modulation, and incorporating with CeO2 to fasten intermediates conversion. As an efficient bifunctional catalyst, PtCe-CeO2/C exhibits the MOR and ORR mass activities 3.6 and 9.4 times of Pt/C, and outperforms in DMFCs. The regulation in electronic structure, intermediate adsorption, and the enhanced catalytic mechanism for MOR and ORR on PtCe-CeO2/C are clarified by experiments and theoretical calculations to comprehend the superiority in catalytic activity. Consequently, this work proposes an innovative strategy for deep electronic regulation of CeO2-modified Pt-based materials by ultra-low-electronegativity Ce to understand the mechanism in electronic structure modulation and promote the reliable operation of DMFCs.