Effective Fabrication and Electrochemical Oxygen Evolution Reaction Activity of Gold Multipod Nanoparticle Core–Cobalt Sulfide Shell Nanohybrids

Abstract

Inorganic hybrid materials with anisotropic noble-metal nanoparticle cores and cagelike transition-metal chalcogenide shells are promising candidates for a wide variety of applications. Herein, we report an effective fabrication method for gold multipod nanoparticle (GMN) core–cobalt sulfide shell (GMN@CoxSy) nanostructures. The unique cagelike morphology is successfully acquired within nanohybrids (GMN@CoxSy nanocages). The cobalt-based metal–organic frameworks can act as versatile sacrificial templates to the desired hybrid nanomaterials through solution-based etching approaches without any undesirable reshaping of GMNs, which are embedded within. Examination of the electrocatalytic oxygen evolution reaction (OER) of the prepared nanohybrids reveals that a type of GMN@CoxSy nanohybrid shows a substantially lower overpotential (η) value (345 mV) compared with those of GMNs (617 mV) and CoxSy nanomaterials (418 mV) at a current density of 10 mA cm–2. The enhanced OER performance is mainly attributed to the highly effective core–shell interfaces stemming from the unique multibranch topologies of the GMN cores as well as the optimized cobalt sulfide shells of the nanohybrids.