Enhanced performance of charge storage supercapattery by dominant oxygen deficiency in crystal defects of 2-D MoO3-x nanoplates

Different colors of partially reduced 2-D MoO3-x-S(1-4)-C nanoplates, converted from the pristine fully oxidized MoO3-5(1-4), were successfully prepared by varying the stirring temperatures followed by constant calcination temperature (x, S, and C indicates oxygen vacancy, stirring temperature, and calcination temperature, respectively). Among these parameters, the reduced 2-D MoO3-x-S4-C nanoplates exhibit the most dominant oxygen deficiency and crystal defects due to the presence of NH4 as reducing agents in AHM precursor at stiring temperature (100 degrees C) with calcination temperature (300 degrees C). The dominant oxygen vacancy concentration of 2-D MoO3-x-S4-C nanoplates presents an extraordinary interlayer spacing and thereby electrical conductivity is improved in electrode materials. In addition, the 2-D MoO3-x-S4-C nanoplates are demonstrated to promote faster charge-storage kinetics and significantly improve the electrochemical activity by exhibiting 573.7 Ahg (-1) at 1 Ag-1 and the 93% of capacitance retention at 5 mVs(-1) after 10,000 cycles. The solid state asymmetric supercapattery of 2-D MoO3-x-S4-C//RGO device exhibits maximum operating potential windows up to 1.6 V, the energy density 129.6 Wh kg(-1) at a power densities of 11.6 kW kg(-1), and 98.6% capacity retention over 10 000 cycles at a scan rate of 50 mV s(-1) in 6 M KOH electrolyte solution.

Automated summary

This study successfully prepared 2-D MoO3-x-S4-C nanoplates with dominant oxygen deficiency and crystal defects through controlled heating and calcination temperatures, demonstrating superior electrical conductivity and electrochemical activity.