Enhanced electrochemical performance of MoSe2 nanosheets on CoAl- layered double hydroxide for oxygen evolution reaction

The design of high-efficiency electrocatalysts for water electrolysis has attracted much attention. A crucial half-reaction in electrochemical water splitting is the oxygen evolution reaction (OER), which suffers from sluggish reaction kinetics due to the high-energy barrier of the complex electron transfer process. This study presents a MoSe2@CoAl-layered double hydroxide (LDH) hybrid nanostructure prepared using the facile hydrothermal method and investigated as a potential OER electrocatalyst. Morphological analysis indicated that the MoSe2 formed in very thin nanosheet structures containing multiple defects on the LDH platelets, increasing the number of catalytic active sites. Compared with pristine MoSe2 and CoAl-LDH, the obtained MoSe2@CoAl-LDH catalyst exhibited enhanced electrocatalytic activity for the OER in an alkaline solution. The MoSe2@CoAl-LDH electrocatalyst showed an overpotential of 360mV at a current density of 10mAcm-2 and a small Tafel slope of 53mV dec-1. In addition, it demonstrated good electrochemical stability. The MoSe2@CoAl-LDH exhibited a lower Tafel slope than commercial RuO2, indicating faster electron transfer on the MoSe2@CoAl-LDH electrode.