Rare Earth-Doped MoS2 for Supercapacitor Application

The low availability of fossil fuels, high expenditure, and serious environmental impacts are the key to sustainable clean and green energy development. Molybdenum-based electrode materials are identified as effective electrodes to improve energy storage devices' performances. In this work, pure and different rare earth (neodymium and gadolinium) doped MoS2 electrodes are successfully prepared by employing the hydrothermal method. Doping rare earth elements with metal sulfides would be beneficial for combining with functional groups due to the 4f vacant orbital. Macroscopic analysis exposed the morphological variations from sphere to sheet by the effect of doping. The sheet-like Gd-doped MoS2 nanostructures exhibited the maximum 357 F/g@10 mV/s specific capacitance from CV and 231.38 F/g@1 A/g from GCD with a prolonged cycling life of 81.50% over 5000 cycles. EIS spectra revealed the lowest solution and charge transfer resistance for Gd-doped MoS2 materials, which suggests the high conductivity of the material. The strategies and results outlined in this paper are expected to trigger the search for completely new rare earth-doped metal sulfides for efficient energy storage applications.