Noble metal decorated Ti3C2Tx MXene for room temperature SO₂ detection

This paper presents an in-depth investigation into the synthesis and characterization of Ti₃C₂Tₓ MXene and its noble metal-decorated variants (Ti₃C₂Tₓ-Ag and Ti₃C₂Tₓ-Au), underscoring their viability for the fabrication of high-performance SO₂ sensors. A self-reduction approach was employed to decorate Ti 3 C 2 T x MXene with noble metals, and comprehensive characterization techniques enabled a detailed analysis of their properties. The formation of multilayered, and delaminated Ti 3 C 2 T x and its successful decoration with Ag and Au nanoparticles (NPs) was confirmed using X-ray diffraction (XRD) analysis. The accordion-like morphology of multilayered Ti 3 C 2 T x and transparent sheet-like structure were observed via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). SO 2 sensing measurements revealed that Ti 3 C 2 T x , along with its Ag- and Au-decorated Ti 3 C 2 T x , demonstrated room-temperature SO 2 sensing with rapid response and recovery times. The loading of noble metals significantly improved sensitivity, with Ag-Ti 3 C 2 T x showing the highest response. Density functional theory (DFT) calculations were performed to elucidate the mechanism underlying the enhanced sensitivity following noble metal decoration. The study results forecast a significant contribution to the development of Ti 3 C 2 T x MXene for gas sensing applications. • Mild etching and self-etching routes are employed to yield Ti 3 C 2 T x MXene and noble metal decorated Ti 3 C 2 T x respectively. • Ag decorated Ti 3 C 2 T x MXene has exhibited 25-fold increment in SO 2 response compared to Ti 3 C 2 T x . • The prepared sensing materials have shown quick response and recovery. • Ag decorated Ti 3 C 2 T x demonstrated response and recovery times of 79 and 63 s, respectively.