Two-Dimensional Titanium Nitride (Ti₂N) MXene: Synthesis, Characterization, and Potential Application as Surface-Enhanced Raman Scattering Substrate

We report on the synthesis, characterization, and application of Ti₂N (MXene), a two-dimensional transition metal nitride of M₂X type. Synthesis of nitride-based MXenes (M_<i>n</i>+1N_<i>n</i>) is difficult due to their higher formation energy from M_<i>n</i>+1AN_<i>n</i> and poor stability of M_<i>n</i>+1N_<i>n</i> layers in the etchant employed, typically HF. Herein, the selective etching of Al from ternary layered transition metal nitride Ti₂AlN (MAX) and intercalation were achieved by immersing the powder in a mixture of potassium fluoride and hydrochloric acid. The multilayered Ti₂NT_<i>x</i> (T is the surface termination) obtained was sonicated in DMSO and centrifuged to obtain few-layered Ti₂NT_<i>x</i>. MXene formation was verified, and the material was completely characterized by Raman spectroscopy, XRD, XPS, FESEM-EDS, TEM, STM, and AFM techniques. Surface-enhanced Raman scattering (SERS) activity of the synthesized Ti₂NT_<i>x</i> was investigated by fabricating paper, silicon, and glass-based SERS substrates. A Raman enhancement factor of 10¹² was demonstrated using rhodamine 6G as the model compound with 532 nm excitation wavelength. Detection of trace level explosives with a simple paper-based SERS substrate with Ti₂N (MXene) as active material was also illustrated

A Novel Biomass Derived Carbon Quantum Dots for Highly Sensitive and Selective Detection of Hydrazine

We report for the first time, carbon quantum dots (CQD) based highly sensitive and selective electrochemical sensor for detection of hydrazine. CQD was synthesized by pyrolysis method using a natural precursor, chia seeds. The sensing ability was studied in terms of oxygen‐rich functional groups present on the surface of CQD