PEI/PEG修饰的MXene/WS₂异质结用于NH3高性能传感研究OA

To address the challenges of industrial pollution and fluctuations in environmental ammonia concentrations,ammonia sensors characterized by low cost,minimal power consumption,a wide detection range,and rapid response have garnered significant attention.In this study,a novel electrochemical sensor was fabricated via an MXene/WS₂ composite functionalized with polyethyleneimine(PEI)/polyethylene glycol(PEG).Characterization results demonstrate that the MXene serves as a two-dimensional conductive framework,while the WS₂ nanosheets provide abundant active sites.The PEI/PEG coating affords abundant-NH2/-OH functional groups,forming a P-N heterojunction structure that significantly enhances the material's gas sensing performance.Under a bias voltage of-0.3 V,the gas-sensing sensor demonstrated a response time of 17.2 s and a recovery time of 26.7 s toward 50 ppm ammonia.Ammonia chemisorbs on functional groups(e.g.,-NH2 and Ti-(OH)ₓ)on the material's surface,forming adducts such as Ti3 C2-NH3.The generation of these groups induces a change in the sensor's resistance.Experimental results demonstrate that the sensor exhibits excellent repeatability and stability(relative error<1%),maintains stable accuracy at 25～35 ° C and 25%～75%relative humidity,and shows good anti-interference ability against O₂,N₂,CO₂,and NO₂.This sensor is suitable for deep-well safety monitoring,indoor and outdoor air quality monitoring,and industrial exhaust gas monitoring.