▎ 摘　　要

The electrochemical performances of sonicated graphene quantum dots dispersoid zinc ammonium phosphate (ZIAMPH @ GQD(x))(sonic) hybrid composites have been investigated for the first time at different variates of x = 25, 50, 75, and 100 mg. The cyclic voltammetry and galvanostatic charge-discharge results have shown quasi-reversibility, and the 50 mg-sonicated composite (ZIAMPH @ GQD(x=50 mg))(sonic) has shown higher specific capacitance of 683 Fg(-1) @ 1 Ag-1 in 2 M H2SO4 than the same variate without sonication. The Dunn method/Randles-Sevcik calculations show higher diffusion and the BET studies reveal higher surface area of 8.896 m(2) g(-1) and pore diameter of 3.45 nm for the sonicated (ZIAMPH @ GQD(x=50 mg))(sonic) than that of the unsonicated. In XRD studies the ZIAMPH(sonic) exists in the mixed crystalline phase (monoclinic/hexagonal), whereas the unsonicated ZIAMPH is in single-crystalline phase (monoclinic). The ZIAMPHGQD2//rGO hybrid device operates within a wider cell voltage of 0-1.8 V in 3 M H2SO4 aqueous electrolyte and renders the higher specific capacitance (306 Fg(-1) @ 1 Ag-1) and high energy density of 138 Wh kg(-1) for the power density of 450 W kg(-1) with the capacity retention of 88% for 5000 charge-discharge cycles and faster relaxation time (tau(0)). The SEM morphology of the sonicated (ZIAMPH @ GQD(x=50 mg))(sonic) shows fluffy cotton locks morphology due to the dimensional, concentration effect of GQD and Microwave irradiation. The XPS and FT-Raman have been advocating the sonication effect and GQD concentration dispersoid at ZIAMPH as the promising electrode for high energy density hybrid supercapacitor applications.