Constructing 2D MOFs from 2D LDHs: highly efficient and durable electrocatalyst for water oxidation
Two-dimensional (2D) materials have been widely applied to electrochemical conversion technologies, especially toward the water oxidation reactions (WOR) in metal-air batteries and water splitting. Here, we demonstrate a facile ligand-assisted synthetic method, promoting the transformation from 2D layered double hydroxides (LDHs) to 2D metal-organic frameworks (MOFs). CoFe-LDH precursor performs as an adjustable metal release source, controlling heterogeneous nucleation for 2D MOFs. Compared with most cobalt-based electrocatalysts, the optimized CoFe 2D MOFs exhibits a superior WOR performance on glassy-carbon electrodes (overpotential of 274 mV at 10 mA cm-2, a Tafel slope of 46.7 mV dec-1) and long-term stability, due to the unique 2D characteristics and coupling effect between Co and Fe ions. More importantly, this work highlights the ability to transformation from 2D LDHs to 2D MOFs, and reveals the intrinsic factors for excellent performance in WOR.
- This article is part of the themed collection: 2019 Journal of Materials Chemistry A HOT Papers