FeSe2/TiO2 heterostructure as an efficient photocatalyst and their electrochemical energy storage applications

This paper reported the facile synthesis of FeSe2 and TiO2 and their different wt.% composites (75 and 50% of TiO2, here after FT-1 and FT-2) via solvothermal in/ex-situ sol-gel method for the first time efficient photocatalytic degradation of Rhodamine removal and supercapacitor applications. Small bandgap energy was obtained for FT-1 samples from the optical analysis, with a more negligible band edge absorption. The result shows that the composite of FeSe2 and TiO2 increases the absorption, which collectively enhances the separation of the charge carriers and redox activities. The photocatalytic activities analysis demonstrated that the FT-1 sample reveals the fastest removal of the RB dye in just 60 min (FT-2, FeSe2, and TiO2 = 90, 100, and 180 min) with good stability (98%) after several cycles. As supercapacitor electrode materials, all electrodes showed well-defined peaks in their CV loops and voltage plateaus in their charge/discharge profile, illustrating the pseudocapacitive charge storage mechanism. No voltage decay was observed during many discharge currents from the charge/discharge investigation, demonstrating the chosen potential frame is a suitable window for the FeSe2 and TiO2 nanomaterials. The higher capacity of 295 (FT-1) than other electrodes (FeSe2, TiO2, and FT-2 = 220, 115, and 240 C/g) at 1 A/g was obtained to reach 180 at 10 A/g, resulting in an enhanced rate capability of 82%. The high rate capability is the cause of its more minor charge transfer resistance, resulting in higher conductivity and supporting rapid charge transport kinetics. These outstanding properties open a new avenue for other FeSe2 and TiO2 nanomaterials for efficient energy storage technologies.