Quenching-Induced Three-Phase Heterostructured Catalysts for Oxygen Electrocatalysis with Lattice Oxygen...

Lattice oxygen-mediated mechanism of oxygen evolution reaction can overcome the scaling relations-induced limitations imposed by conventional adsorption evolution mechanism, but faces challenges in maximizing activation of lattice oxygen species. The flexible structure of three-phase heterostructured catalysts provides the possibility for high-performance electrocatalysis, yet still face the bottleneck of synthesis difficulty and insufficient regulation. Herein, a facile quenching route is proposed for the synthesis of core-shell catalysts, and the influence mechanism of three-phase heterostructure on quenching engineering is elucidated. High-temperature LaNiO₃ nanoparticles are quenched in FeSO₄ solution to construct a LaNiO₃/Fe(OH)₃ core-shell structure by inducing rapid hydrolysis of Fe²⁺. The differential thermal expansion coefficient between LaNiO₃ and Fe₂O₃, as well as the three-phase interfaces composed of core-shell structure and amorphous/crystalline phases in Fe₂O₃ shell, result in significant surface/interface regulation for LaNiO₃/Fe₂O₃ core-shell catalysts during re-quenching in Co(NO₃)₂ solution, including richer lattice distortion and defects, and more heteroatom doping. The derived three-phase heterostructured catalysts exhibit significantly improved oxygen electrocatalytic activity with lattice oxygen participation, and the assembled liquid zinc-air batteries show excellent output power density and cycling performance. Our finding provides important insights into the synthesis of three-phase heterostructured catalysts and the regulation of heterogeneous interfaces through quenching engineering.