Hierarchical NiCo-LDH@MoS2/CuS composite as efficient trifunctional electrocatalyst for overall water splitting and asymmetric supercapacitor

The development of highly active and long-lived multifunctional electrocatalysts is a key priority to boost clean renewable energy technologies. It is difficult to construct such hierarchically structured materials with an efficient synergistic heterostructure technique to improve electrochemical performance. Here, a novel hierarchical NiCo-LDH@MoS2/CuS heterostructure (HS) was prepared by facile two-step hydrothermal synthesis for water splitting and supercapacitor applications. The hierarchical network of NiCo-LDH is grown on MoS2/CuS and is put forward based on various physio-chemical analysis. The hierarchical structure and heterostructure synergistic effect result in excellent HER (114 mV@10 mA cm(-2)) and OER (310 mV@10 mA cm(-2)) activity. Two electrode water-splitting cells (NiCo-LDH@MoS2/CuS parallel to NiCo-LDH@MoS2/CuS) achieved a cell potential of 1.57 V@10 mA cm(-2). NiCo-LDH@MoS2/CuS also exhibits the electrochemical charge storage property of 147.16 mAh g(-1)@0.2 A g(-1). NiCo@MoS2/CuS parallel to AC flexible solid-state asymmetric supercapacitor (FSSC) demonstrated charge storage of 226.08 mAh g(-1) and energy density of 152.60 W h kg(-1)@0.2 A g(-1) with 90.05 % retention rate, demonstrated the excellent cyclic and structural stability. The acquired knowledge from this study could be a novel strategy for designing hierarchical LDH-based heterostructures as electrode materials for water splitting and energy storage devices.

Automated summary

In this study, a novel hierarchical NiCo-LDH@MoS2/CuS heterostructure was prepared by facile two-step hydrothermal synthesis, exhibiting excellent electrochemical performance in water splitting and supercapacitor applications.