Construction of a Ni2P/NiSe2/MoSe2 hybrid for advanced supercapacitors

MoSe2 has gained significant attention in the field of supercapacitors due to its unique properties and large interlayer spacing. However, the restacking of MoSe2 nanosheets often leads to a decrease in energy storage capacity. To address this issue, this paper presents a synthesis method for a Ni2P/NiSe2/MoSe2 hybrid, referred to as NNM. In this hybrid, Ni2P and NiSe2 nanoparticles are embedded within the MoSe2 nanosheets, effectively increasing the interlayer distance of MoSe2. This architecture exposes more active sites and enhances electron transfer, improving reaction kinetics and electrochemical properties. Compared to individual MoSe2, Ni2P, or NiSe2, the specific capacitance of the NNM hybrid was significantly enhanced, achieving a specific capacitance of 607.5 F/g at a current density of 0.5 A/g. Furthermore, the Ni2P/NiSe2/MoSe2//activated carbon hybrid supercapacitor (labeled as NNM//AC) achieved a specific capacitance of 66.1 F/g at a current density of 0.5 A/g, along with an energy density of 23.5 Wh/kg at 400 W/kg. Impressively, this device demonstrated a retention of 116.6 % after 45,000 cycles at 3 A/g, highlighting its remarkable cyclic durability. This work presents a straightforward method for preparing MoSe2-based nanohybrids for advanced supercapacitors.