Highly stable Ti₃C₂T_x (MXene)/Pt nanoparticles-modified glassy carbon electrode for H₂O₂ and small molecules sensing applications

Electrochemical performance of a 2D Ti₃C₂T_x (MXene, where T: [dbnd]O, –OH, –F) sheets modified with Pt nanoparticles (PtNPs) was investigated. The results showed that Ti₃C₂T_x/PtNP nanocomposite deposited on the surface of GCE showed much better and stable redox behavior in an anodic potential window as compared to the GCE modified with pristine Ti₃C₂T_x MXene. For example, the H₂O₂ sensor of Ti₃C₂T_x/PtNP on GCE offered LOD of 448 nM with a potential at which reduction starts of ∼+250 mV (vs. Ag/AgCl) in comparison to values of 883 μM and ∼−160 mV observed for Ti₃C₂T_x modified GCE. Moreover, the Ti₃C₂T_x/PtNP sensor could detect small redox molecules such as ascorbic acid (AA), dopamine (DA), uric acid (UA) and acetaminophen (APAP) at a potential higher than +250 mV with high selectivity and LOD down to nM level. We proved that selectivity of detection of such molecules (AA, DA, UA and APAP) could be modulated to high extent using external membranes.