Phosphorus doped molybdenum disulfide regulated by sodium chloride for advanced supercapacitor electrodes.

As a pseudocapacitor electrode material, molybdenum disulfide (MoS) usually shows inferior capacity, rate capability and cyclability. Structural regulation and heteroatom doping are the available methods to ameliorate the electrochemical properties of MoS. Herein, phosphorus doped molybdenum disulfide regulated by sodium chloride (SP-MoS) is successfully synthesized using phosphomolybdate acid as a molybdenum source and an dopant and sodium chloride (NaCl) as a structural regulator. Under the structural regulation of NaCl, the SP-MoS nanosheets exhibit an interweaved architecture with a large interlayer spacing of 0.68 nm. Owing to the P doping and large specific surface area (21.0 m g), the SP-MoS electrode possesses a maximum capacity of 564.8 F g at 1 A g and retains 56.3% of the original capacity at 20 A g. Density functional theory (DFT) calculations indicate that SP-MoS displays a high K average adsorption energy of -3.636 eV. In addition, the fabricated SP-MoS//AC asymmetric supercapacitor device displays an energy density of 22.8 W h kg at 759 W kg.