- P-ISSN 1225-0163
- E-ISSN 2288-8985
In this study, ozone (O3) samples were prepared for investigating the heterogeneous reactions between O3 and tropospheric aerosols and were characterized by spectroscopic methods. O3 generated from an ozone generator was purified by selective adsorption on refrigerated silica gel, followed by transfer to a sample bulb. The amount of UV light (λ = 256 nm) absorbed by O3 was measured as a function of time at two different temperatures (room temperature and 50 °C) and under different irradiation conditions. A correlation plot of 1/[O3] versus time showed that O3 decomposition follows the 2nd order reaction rate under a steady-state approximation. The initial concentration of O3, observed rate constants (kobs), and the half-life of O3 in the sample stored at room temperature were determined to be 2.74 [±0.14] × 1016 molecules·cm−3, 4.47 [±0.64] × 10−23 molecules−1·cm3·s−1, and 9.5 [±1.4] days, respectively. The evaluation of O3 stability under various conditions indicated that special care should be taken to prevent the exposure of the O3 samples to hightemperature environment and/or UV radiation. This study established a protocol for the preparation of highly purified O3 samples and confirmed that the O3 samples can be stored for a day after preparation for further experiments.
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