Insights into the effects of Pt and PtOx site for electrocatalytic water gas shift reaction via altering supports and calcinated temperatures.

Electrocatalytic water-gas shift reaction (EWGSR) at room temperature and atmospheric pressure is an emerging process for high-pure hydrogen production without an additional H 2 separation procedure. Therefore, developing efficient electrocatalysts of EWGSR is one of the critical factors for its wide applications. Herein, the effects of support and calcinated temperature on the EWGSR performance are highlighted by systematically investigating the Pt/γ-Fe 2 O 3 , Pt/CeO 2 , Pt/TiO 2 , and Pt/α-Fe 2 O 3 catalysts. The results reveal that the γ-Fe 2 O 3 supported Pt catalyst (calcined at 400 °C) exhibits the lowest anodic onset potential and the highest activity compared to these prepared catalysts, and the mass activity is 3.5 times as high as 20% Pt/C. Furthermore, the onset potential for the EWGSR shows a strong correlation with the active O in the amorphous PtOx structures, where the active O atoms can promote the activation of the OH− and reduce the onset potential of the reaction. The significantly enhanced catalytic performance and durability are more responsible for the exposed Pt0 and the weak adsorption of CO on the Pt/γ-Fe 2 O 3 catalyst. This study provides a new and promising route for designing excellent Pt catalysts for EWGSR in the hope that it can be helpful to the scholars in this orientation. [Display omitted] • The Pt/γ-Fe 2 O 3 presents the lowest onset potential and best reactivity for EWGSR. • The Pt/γ-Fe 2 O 3 possesses the Pt0 coupled PtOx with an active oxygen site. • The reduced onset potential is responsible for the active O in PtOx structure. • The enhanced activity is positive relative to the weak absorption of CO. • The Pt0 coupled PtOx serves as the optimal active site for EWGSR. [ABSTRACT FROM AUTHOR]