Efficient Cataluminescence Sensor for Detecting Methanol Based on NiCo₂O₄//MIL-Ti₁₂₅ Polyhedral Composite Nano-Materials

Since methanol has a significant health hazard due to its inherent toxicity, it is urgent to develop a method capable of rapid, sensitive, and continuous monitoring of methanol. The present study successfully synthesized a NiCo₂O₄/MIL-Ti₁₂₅ composite material and conducted a comprehensive analysis of its effectiveness for the detection of methanol employing cataluminescence (CTL) technology. The findings demonstrated that the composite material displays marked CTL in response to methanol, showcasing notable sensitivity, selectivity, and stability. The composite’s heterogeneous structure significantly improves the adsorption and reaction efficiency of methanol and further reduces the sensor’s working temperature. Under the optimal conditions of 215 °C and a flow rate of 300 mL/min, the CTL signal intensity is governed by the equation Y = 10.388X − 4.473 (R² = 0.982), with a detection limit as low as 0.431 ppm. The NiCo₂O₄/MIL-Ti₁₂₅ sensor exhibits high selectivity towards methanol. In addition, a relative standard deviation (RSD) of 4.95% demonstrates its excellent stability. Utilizing X-ray photoelectron spectroscopy (XPS), the study investigated the impact of elemental valence changes on the CTL process. We believe that the NiCo₂O₄/MIL-Ti₁₂₅ composite material, as a high-performance low-temperature CTL methanol sensor, is promising for applications.