Toward new energy storage devices: Electrochemical and photovoltaic performance of SnSe/Fe, SnSe/Ni nanospherical composites

Nanospherical composites (NSC) of SnSe/Fe and SnSe/Ni were synthesized by co-precipitation technique and analyzed for supercapacitor (SC) and photovoltaic material for energy storage devices. The XRD confirms the orthorhombic crystal structure of SnSe/Fe and SnSe/Ni NSC. The morphology analysis shows that SnSe/Fe and SnSe/Ni NSC change spherical shapes into ball-like structures. The direct energy bandgap values of SnSe, SnSe/Fe and SnSe/Ni NSC are 2.8 eV, 2.6 eV and 2.1 eV, respectively. The SnSe/Ni electrode exhibited the highest specific capacitance of 1253 F/g at the scan rate of 10 mV/s which is higher than SnSe/Ni (935 F/g) and pure SnSe (703 F/g) electrodes, respectively. Additionally, SnSe/Ni electrodes shows excellent energy density values 25 Ws/g than SnSe/Ni (17.5Ws/g) and pure SnSe (12.5 Ws/g) electrodes, corresponding to power density 2.5 W/g, respectively. Under stimulated solar light irradiation with an intensity of 1.5 AM, the dye-sensitized solar cells (DSSCs) based on NiSnSe hybrid counter electrode (CE) achieves a power conversion efficiency (PCE) of 10.30 % which is higher than that of FeSnSe, SnSe and conventional platinum (Pt) CEs, respectively.