▎ 摘　　要

We have synthesized with and without graphene quantum dots (GQDs) supported Molybdenum sulfide (Mo3S4/GQDs) by the hydrothermal route and examined the effect on electrochemical and dye sensitized solar cells (DSSCs) performance. The crystalline structure and composition are elucidated by X-ray diffraction and X-ray photoelectron spectroscopy, respectively. The synthesized samples show a spherical nature which is confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). JV spectra reveal GQDs modified Mo3S4 counter electrodes deliver the highest short circuit current (J(SC)) of 13.84 mA cm(-2), open-circuit voltage (V-OC) of 0.72 V, and power conversion efficiency (PCE) of 5.67%, which is 13% higher compared to pristine counter electrodes. Low peak to peak separation (Epp) and higher peak current density (Jpc) and exchange current density (Jo) are responsible for this improvement. Besides, the samples have been employed as a working electrode and studied supercapacitor performance. Among them, Mo3S4/GQDs exhibited the highest specific capacitance of 234 F g(-1) at 2 A g(-1). The results mentioned above reveal GQDs supported Mo3S4 is not only a viable substitute for Pt-free counter electrodes but also provide a better outlook for energy storage devices. (C) 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited.