Abstract
Through one-pot hydrothermal synthesis, we synthesized VSe2-CoSe2 nanostructures with a distinctive flower-like morphology. The structural characterizations were conducted using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy (FTIR). By modulating the proportion of the CoSe2 phase, we transformed these hybrid nanostructures into nanoparticles, thereby influencing their nonlinear optical properties. The third-order nonlinear optical parameters (n 2 and β) were rigorously examined via the precise Z-scan technique under various laser power conditions. The nanostructures demonstrated a self-focusing refractive response and exhibited pronounced two-photon absorption during the nonlinear absorption process. The magnitudes of n 2 and β were determined to be in the order of 10-8 (cm2 W-1) and 10-4 (cm W-1), respectively. The exceptional figure of merit (FOM) of these composite flower-like structures underscores their superior nonlinear optical characteristics, establishing them as promising candidates for photonic applications, particularly in optical switching devices.