Abstract

In this study, graphene oxide, lanthanum sulfide and their composite thin films are prepared using simple and inexpensive chemical methods and their supercapacitive performance is evaluated. The X-ray diffraction study shows the formation of mixed-phase lanthanum sulfide with monoclinic α-LaS₂ and tetragonal La₅S₇. Field emission scanning electron microscopy images show porous surface morphology of lanthanum sulfide and composite thin films. The supercapacitive performance of composite film tested in 1 M Na₂SO₄ electrolyte shows highest specific capacitance of 312 F g⁻¹ at a 5 mV s⁻¹ scan rate.