A pyridine vapor sensor based on metal-organic framework-modified quartz crystal microbalance

•A synthesized NMOF of Al(OH)(1,4-NDC) was successfully assembled on the surface of QCM.•A new QCM sensor indicates high sensitivity and the selectivity for pyridine vapor detection.•Adsorption mechanism of pyridine in Al(OH)(1,4-NDC) was studied by van der Waals corrected density functional theory calculation. A novel pyridine vapor sensor has been prepared by modifying the Quartz crystal microbalance (QCM) with nanoscale metal-organic framework (NMOF, named as Al(OH)(1,4-NDC)). The preparation conditions for the sensor were optimized. Improved sensing performance was achieved by using dichloromethane (CH2Cl2) instead of N,N-dimethylformamide (DMF) to disperse the NMOF on the QCM. In addition, the sensor’s sensitivity was greatly enhanced by increasing the load of NMOF. A good linear relationship was obtained (ln(△f)=6.403+0.434 lnC, R2=0.99876) in the range of 0.3–25ppm of pyridine. The sensor exhibited high selectivity, repeatability and long-term stability for pyridine detection. The adsorption mechanism of pyridine on sensor was studied by van der Waals corrected density functional theory calculation. The recovery ratio of the pyridine vapor sensor was 97.5–108.7%.