Single-component MXene-based sensor array generates independent and high-dimensional characteristics for discriminating volatile organic compounds
The discrimination of volatile organic compounds (VOCs) at trace concentrations remains a critical challenge for environmental monitoring, industrial process control, and non-invasive disease diagnostics. Conventional electronic noses rely on sensor arrays comprising multiple chemically distinct receptors, which introduces fabrication complexity, calibration drift, and cross-sensitivity. Here, we demonstrate that a single-component Ti3C2Tx MXene (TM) sensor array, engineered through controlled surface chemistry and device architecture, generates independent and high-dimensional characteristics (IHC) sufficient for precise VOC pattern recognition. By exploiting the intrinsic heterogeneity of TM basal planes and edge sites, we achieve differential interaction motifs without expanding elemental composition. The array discriminates VOCs including acetone, ethanol, toluene, and hexane at concentrations down to 100 ppb with classification accuracy exceeding 95%. Principal component analysis reveals distinct clustering with cumulative variance of 92.3% captured by the first three principal components. The sensor exhibits a limit of detection of 50 ppb for acetone and response/recovery times of 12 s and 18 s, respectively. Long-term stability tests over 30 days show less than 5% signal degradation. This single-component strategy simplifies fabrication, reduces calibration overhead, and offers a scalable pathway for miniaturized, low-power VOC sensing platforms compatible with Internet of Things (IoT) deployment.