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High-performance catalysts are crucial for many applications, including high-performance gas sensors. However, the catalysts used in gas sensors need to be screened through many experimental measurements, which is time-consuming and labor-intensive. Herein, the catalytic activity of ZSM-5 zeolites with different Si/Al ratios is quantitatively evaluated using a resonant microcantilever that enables in-situ temperature-programmed desorption (cantilever-TPD) measurements. Since the frequency shift obtained by the cantilever-TPD measurement is proportional to the number of probe molecules, the cantilever-TPD experiment can successfully measure the number of active sites and desorption activation energy of the catalyst. Therefore, the cantilever-TPD experiment quantitatively characterizes the catalytic activity through the comprehensive analysis of the number of active sites and the desorption activation energy, eliminating the need for the traditional trial-and-error method to study the gas-sensing performance. According to the test results of cantilever-TPD, the ZSM-5 zeolite with satisfactory performance is preferred as the catalytic material, and the ZnO/ZSM-5 double-layer sensor is made to detect trace amounts of the greenhouse gas Freon R134a. The gas sensing results show that the optimized ZSM-5 sensor has good sensitivity, limit of detection (LOD), repeatability, and selectivity, fully confirming the evaluation results of the cantilever-TPD. • Resonant microcantilever is used for TPD measurements of catalytic-induced sensing materials. • The catalytic activity of ZSM-5 zeolites with different Si/Al ratios has been quantitatively evaluated. • ZSM-5 zeolite, with satisfactory performance, was selected as the catalytic-induced sensing material. [ABSTRACT FROM AUTHOR]

[Display omitted] • Local environment of oxygen vacancies at MnO 2 were regulated by the concentration of Mo doping. • Moderate Mo doping could generate effective oxygen vacancies Mn-Ov-Mo. • 0.3MoMnO 2 with abundant Mn-Ov-Mo sites exhibited excellent catalytic activity, cycling stability, and toxicity resistance. • Mn-Ov-Mo sites facilitate the dynamic equilibrium of oxygen adsorption and desorption, promoting the activation of O 2. The microenvironment of oxygen vacancies plays an important role in metal oxide catalysts for VOCs catalytic oxidation. A simple strategy was provided to tailor the local environment of oxygen vacancies over MnO 2 via Mo doping engineering to enhance its catalytic activity. The 0.3MoMnO 2 with Mo/Mn quality ratio of 0.3 showed superior catalytic oxidation performance of benzene and anti-toxicity (H 2 O, SO 2, and particulate matter). Its benzene oxidation rate at 190℃ was 1.95 × 10−4 mol/g/h, which was about three and two times higher than that of MnO 2 and 0.9MoMnO 2 , respectively. The Mn-Ov-Mo sites were experimentally verified as the dominant active centers on 0.3MoMnO 2. Through DFT calculation, Mo doping could enhance the oxygen adsorption on oxygen vacancies of MnO 2. The remarkably well activity of Mn-Ov-Mo was rationally explained by the moderate oxygen adsorption energy to maintain a dynamic equilibrium of oxygen adsorption and desorption, which enhanced the oxygen activation, thereby promoting the benzene catalytic oxidation. However, excessive Mo doping induced the formation of Mo-Ov-Mo, and its side-on oxygen adsorption configuration was not conducive to oxygen transfer. This work broadens the understanding of the relationship between the local environment of oxygen vacancies and catalytic activities, which is beneficial for the rational design of efficient VOCs catalysts. [ABSTRACT FROM AUTHOR]