Microwave‐assisted one‐pot synthesis of MXene–rGO–Au nanocomposites for high‐sensitivity dopamine detection

Abstract A rapid, single‐step microwave‐assisted hydrothermal method was developed for synthesizing a Ti 3 C 2 T x MXene–reduced graphene oxide–gold nanoparticle (MXene/rGO/AuNP) ternary nanocomposite, completed in 20 min at 120°C. This method eliminates the need for multistep processing while facilitating the in situ integration of AuNPs within a conductive MXene/rGO framework. Structural and morphological analyses confirmed the presence of AuNPs and the formation of an interconnected heterostructure with a high electroactive surface area. Electrodes modified with MXene/rGO/AuNPs demonstrated accelerated dopamine (DA) oxidation kinetics, as shown by cyclic voltammetry and differential pulse voltammetry. Composition optimization identified MXene/rGO/10 wt.% AuNP as the optimal configuration, achieving a detection limit of 0.176 µM and a linear response range of 4–32 µM. The performance enhancement is attributed to coupled charge transport across MXene basal planes, π–π interactions, and adsorption sites provided by rGO, and catalytic electron‐transfer pathways mediated by AuNPs. The sensor maintained selectivity in the presence of common interferents and achieved recovery values of 93.00%–100.60% in real‐sample matrices, confirming its analytical reliability. This strategy offers a time‐efficient approach to hierarchically integrated MXene‐based heterostructures and demonstrates their utility for sensitive electrochemical neurotransmitter detection.