2D/0D Heterojunction Fluorescent Probe with Schottky Barrier Based on Ti₃C₂T_X MXene Loaded Graphene Quantum Dots for Detection of H₂S During Food Spoilage

Abstract Hydrogen sulfide (H₂S) contamination of food has raised widespread public health concerns, leading to substantial medical and economic burdens. Herein, a 2D/0D heterojunction fluorescent probe (TCTG) with Schottky barriers (SB) is designed and synthesized, utilizing Ti₃C₂T_x MXene‐loaded graphene quantum dots (GQDs), for the detection of H₂S during food spoilage. The microstructures observed through SEM and TEM reveal that uniformly sized GQDs are evenly attached to the surface of a monolayer Ti₃C₂T_x. The chemisorption between GQDs and Ti₃C₂T_x facilitates charge transfer and the formation of SB, resulting in intramolecular charge transfer (ICT) effects. With the introduction of H₂S, TCTG_(50%) exhibits the highest sensitivity, selectivity, and anti‐interference properties, with ultra‐fast fluorescence transient reaction (3s) and remarkably low detection limit of 41.82 ppb as well as noticeable color change. When TCTG_(50%) reacted with H₂S, the ICT effects are inhibited, leading to the recovery of photoinduced electron transfer (PET) and fluorescence quenching. Notably, probe TCTG is effectively utilized to detect changes in H₂S levels in raw foods to assess their quality. Overall, the significance of this study is its potential to revolutionize food spoilage detection, offering a fast, reliable, and sensitive method to ensure food safety and reduce associated health and economic burdens.