Designing ultrathin single and multilayered Ti3C2TX MXene as photocatalysts for enhanced acetaminophen degradation in Photo-Fenton-like reactions

Acetaminophen (ACTP) is a widely used antipyretic and analgesic, especially after the COVID-19 pandemic, during which its extensive use led to widespread distribution in the environment. Conventional wastewater treatment methods struggle to fully degrade ACTP, posing potential risks to human health and ecosystems. Therefore, developing efficient, safe, environmentally friendly, and cost-effective techniques for ACTP degradation is imperative. Herein, ultrathin-single Ti 3 C 2 T X MXene (USM) and multilayered Ti 3 C 2 T X MXene (MLM) with nanometer thickness and micron transverse size were synthesized from the MAX via acid/salt (HCl + LiF) etching process. Time-resolved photoluminescence indicated that the average fluorescence lifetimes (τ ave ) of USM (96.870 ns) and MLM (53.839 ns) are 9.47 and 5.26 times that of MAX (10.229 ns), respectively. Both materials exhibited excellent ACTP degradation ability (∼100 %) in a photocatalytic Fenton-like reaction process under visible light within 60 min. The visible light enhanced the degradation of ACTP by accelerating the redox cycles of Ti 3+ /Ti 4+ and achieving continuous catalytic activation of H 2 O 2 to form reactive oxygen species (h + , •OH, •O 2 – , and 1 O 2 ). Among these, h + radicals were the primary contributors, with •OH, •O 2 – , and 1 O 2 also playing supportive roles in the degradation process. The ecological structure–activity relationships analysis indicated that the degradation intermediates had significantly lower toxicity than ACTP itself. This study offers valuable insights into MXene’s application in photocatalytic Fenton-like systems, paving the way for efficient pharmaceutical degradation.