Temperature-Modulated Eu-Doped Gd₂O₃ Cataluminescence Sensing Platform for Selective Detection of Isomeric and Homologous Alcohols

The selective and rapid identification of alcohol vapors, including isomers and homologues, is crucial for environmental monitoring and industrial safety. Herein, a high-performance cataluminescence (CTL) sensing platform based on Eu-doped Gd₂O₃ was developed to discriminate alcohol vapors. Temperature-modulated CTL responses were employed to encode both thermodynamic and kinetic information, generating distinctive molecular fingerprints for tested alcohols to enable effective substance differentiation. Specifically, the novel fingerprints, derived from the ratio of CTL signals to CTL time of Gd₂O₃:3%Eu at variable temperatures, successfully discriminated six alcohols─MeOH, EtOH, NPA, IPA, NBA, and IBA. The detection limits for these analytes were 0.024, 0.026, 0.058, 0.018, 0.072, and 0.016 μg mL^-1, respectively. Moreover, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) provided real-time insights into the dynamic adsorption and catalytic oxidation behaviors of alcohols across varying temperatures. This work presents a novel temperature-modulated CTL fingerprinting strategy, offering an effective approach for distinguishing isomers and homologues from similar volatile organic compounds.