Engineering hierarchical CoSe/NiFe layered-double-hydroxide nanoarrays as high efficient bifunctional electrocatalyst for overall water splitting
Abstract
Exploitation of earth-abundant, cost-effective and high-efficient bifunctional electrocatalysts for overall water spitting in basic media is highly desirable, yet it remains a big challenge. Here, NiFe Layered-double-hydroxide nanosheet-anchored CoSe nanotubes (composed of plicated nanosheets) supported on Ni foam are prepared through our developed hydrothermal-selenization-hydrothermal method. Benefiting from the unique nanoarchitecture, optimized adsorption/desorption of oxygenated species at the interface (owing to the re-delocalization of electron spin status via π-donation), the bifunctional hybrid catalysts exhibit low overpotentials of 201 and 98 mV at 10 mA cm-2 for oxygen evolution reaction and hydrogen evolution reaction in 1 M KOH aqueous solution, respectively. Particularly, the full-cell only requires 1.53 V to drive a current density of 10 mA cm-2 when choosing the hybrid catalysts serving as both anode and cathode, being superior than that of the state-of-the-art commercial noble-metal based cells for overall water splitting. This work presents a general strategy to boost the oxygen evolution reaction and hydrogen evolution reaction kinetics of selenides, which is also expected to extend to other noble-metal-free catalysts.
- Publication:
-
Journal of Power Sources
- Pub Date:
- June 2019
- DOI:
- 10.1016/j.jpowsour.2019.04.014
- Bibcode:
- 2019JPS...425..138S
- Keywords:
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- Bifunctional electrocatalyst;
- Interface;
- Water splitting;
- Selenides;
- Layered double hydroxides