V-Ag doped ZnO nanorod as high-performance electrode material for supercapacitors with enhanced specific capacitance and cycling stability

In this present work, we synthesized the V-Ag co-doped ZnO nanorods for high performance supercapacitors using one step sol-gel method. The influences of the doping (V and Ag) on the morphological, structural characteristics, electrochemical performance, and long term cycle of ZnO upon redox was investigated for their applicability in SCs. The XRD results revealed to the crystallite sizes of pure ZnO, V0.03Ag0.03ZnO, V(0.0)5Ag(0.05)ZnO, and V0.07Ag0.07ZnO samples were in the ranges of 32.79, 11.37, 9.30, and 8.60 nm, respectively. The HR-SEM and HR-TEM images revealed similar nanorod morphology. The appearance of Zn, Ag, V, and O was confirmed from the EDX and XPS analysis of the V0.07Ag0.07ZnO nanorods without any observation of additional peaks. The CV results validated the pseudocapacitive nature of the synthesized electrodes. The highest specific capacitance was attained for the V0.07Ag0.07ZnO electrode was recorded as 2700.19 Fg(-1), which is higher than ZnO (402.1 Fg(-1)) values. The GCD curves of V0.07Ag0.07ZnO electrode demonstrated remarkable charging-discharging capabilities, with cyclic retention of 93% at 1 A/g. These excellent performances of the V0.07Ag0.07ZnO electrode material make them highly appealing to future energy conversion and storage systems. (c) 2021 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.