Highly porous ruthenate pyrochlore with ultrasmall Ru nanoparticles and a P dopant for efficient oxygen evolution electrocatalysts in an alkaline medium.

[Display omitted] • Highly porous pyrochlore oxide was synthesized by controlling the temperature of sol–gel process. • Ru nanoparticle anchored on YRO pyrochlore was synthesized by simple In situ exsolution. • Metal-support structure with ultrasmall Ru nanoparticle enhances OER catalytic activity. • Introduction of P dopant changes the electronic structure around metal atoms, enhancing catalytic activity. To enhance green energy technologies, such as metal–air batteries, designing a highly efficient electrocatalyst for the oxygen evolution reaction is crucial because of its sluggish kinetics. In this study, pyrochlore oxide was uniquely synthesized with ultrasmall Ru nanoparticles, a highly porous structure, and a P dopant via simple in situ exsolution, resulting in an outstanding intrinsic activity and surface area. The porous structure of pure pyrochlore was optimized by controlling the temperature of the cross-linking process. The pyrochlore cross-linked at 80 ℃ (YRO-80) had the highest Brunauer-emmett-Teller (BET) surface area (186.1 m2/g). Ultrasmall Ru nanoparticles anchored on Y 2 R 2 O 7 pyrochlore with the P dopant (Ru/YRO-P) were simply synthesized using a one-step process. The high electrocatalytic performance of Ru/YRO-P was demonstrated by its low overpotential (232 mA/cm2), low Tafel slope (41 mV/dec), and high power density (179.2 mW/cm2) in Zn–air battery applications. This paper presents a rational design strategy for enhanced electrocatalysts. [ABSTRACT FROM AUTHOR]