HF-assisted one-step synthesis of pompon-like/chip-like FeSe2 particles and their superamphiphobic/antireflective property

Hydrofluoric acid (HF)-assisted one-step synthesis of pompon-like/chip-like FeSe2 particles by a solvothermal method has been studied for the first time in this paper. By adjusting the dosage of HF used, FeSe2 particles with pompon-like and chip-like morphologies were obtained. The reaction mechanism was presented based on the experimental phenomena, and the roles played by HF in the synthesis were clearly explained, proving that HF had a significant influence on controlling the morphologies of the FeSe2 particles. By altering the iron sources without changing any other conditions (similar experimental results were observed). We further demonstrated that this method was universally applicable. The wettability and light-trapping effects of the pompon-like/chip-like particles were also investigated, respectively. After modification with heptadecafluorodecyltrimethoxy-silane (HTMS), the pompon-like particles exhibited excellent superhydrophobic/superoleophobic (superamphiphobic) properties with water/oil contact angle of about 156.0 degrees/154.6 degrees and water/oil sliding angle of about 2.0 degrees/5.0 degrees. Ultralow reflectance of the samples (lower than 3%) in the entire wavelength range of 300-1800 nm was also observed in our experiments. Utilizing HF to control the morphologies of FeSe2 particles is an innovative attempt and is expected to show promising potential in controlling the morphologies of other transition metal chalcogenides.