2D TiS2 Flakes for Tetracycline Hydrochloride Photodegradation under Solar Light

Here, we report a simple route of synthesizing bulk layered TiS2 via chemical vapor transport (CVT) using non-toxic inorganic precursors, followed by successful isolation of few-layered TiS2 flakes using high-frequency-based liquid-phase exfoliation. Exfoliated TiS2 flakes exhibit significantly enhanced photocatalytic activity towards the degradation of tetracycline hydrochloride (TCH) under simulated solar light irradiation, achieving ~ 95% degradation efficiency with its reaction rate constants six times higher than that of the bulk counterpart. The underlying degradation mechanism can be attributed to the fully exposed reactive sites originating from the well-defined layered structure. Trapping experiments coupled with electron paramagnetic resonance (EPR) measurements confirm the generation of electrons and hydroxyl radicals as major active species. The photodegradation pathway and intermediates of TCH were studied in-depth through liquid chromatography-mass spectrometry (LC-MS). The current work provides new insight into using exfoliated TiS2 for environmental remediation.