Co9 S8 Nanoparticles-Embedded N/S-Codoped Carbon Nanofibers Derived from Metal-Organic Framework-Wrapped CdS Nanowires for Efficient Oxygen Evolution Reaction.

ABSTRACT

Metal-organic frameworks (MOFs) with tunable compositions and morphologies are recognized as efficient self-sacrificial templates to achieve function-oriented nanostructured materials. Moreover, it is urgently needed to develop highly efficient noble metal-free oxygen evolution reaction (OER) electrocatalysts to accelerate the development of overall water splitting green energy conversion systems. Herein, a facile and cost-efficient strategy to synthesize Co9 S8 nanoparticles-embedded N/S-codoped carbon nanofibers (Co9 S8 /NSCNFs) as highly active OER catalyst is developed. The hybrid precursor of core-shell ZIF-wrapped CdS nanowires is first prepared and then leads to the formation of uniformly dispersed Co9 S8 /N, S-codoped carbon nanocomposites through a one-step calcination reaction. The optimal Co9 S8 /NSCNFs-850 is demonstrated to possess excellent electrocatalytic performance for OER in 1.0 m KOH solution, affording a low overpotential of 302 mV to reach the current density of 10 mA cm-2 , a small Tafel slope of 54 mV dec-1 , and superior long-term stability for 1000 cyclic voltammetry cycles. The favorable results raise a concept of exploring more MOF-based nanohybrids as precursors to induce the synthesis of novel porous nanomaterials as non-noble-metal electrocatalysts for sustainable energy conversion.