Controllable Constructing Janus Homologous Heterostructures of Transition Metal Alloys/Sulfides for Efficient Oxygen Electrocatalysis

摘要

Constructing novel heterostructures is an effective way for enhancing theoxygen electrocatalytic properties of the catalysts. In this work, a class ofJanus homologous heterostructures, compositing transition metal alloys withtheir corresponding sulfides (TM/TMS), are controllably synthesized throughan ultrafast high-temperature shock (HTS) strategy. The ultrafast sinteringrate and carbothermal reduction reaction lead to the formation of sulfides andpartial reduction of sulfides to alloys, while the ultrafast cooling rate keepsthe homologous heterostructure of TM/TMS stable. The components of TMsin the composites can be well controlled from unary to quaternary. Moreover,benefiting from the synergistic effect of the metallic sites in the interfaces,the adsorption and desorption energy barrier of the active intermediates aresignificantly optimized and thus leading to the enhanced oxygen catalyticperformance. Impressively, the aqueous zinc-air battery (ZAB) using thebinary homologous nanocomposite FeCo/(FeCo)S as air cathodes achievesimpressive durability (> 470 cycles) and power density (261.8 mW cm~(?2)).The as-assembled flexible ZAB can well power the wearable devices and canwork for at least 300 cycles without obvious degradation. This work opensa new chemical space for designing homologous heterostructures for theirapplication in energy storage and conversion systems.