Calibration and counting efficiency evaluation of condensation particle counters using the silver particle generator as a stable source of inorganic salt aerosols
Year: 2025
Type: article
Abstract: This study assesses a facile method to produce stable, inorganic aerosols (NaCl, NaI, KCl, LiCl) for calibrating condensation particle counters (CPCs) expanding the functionality of the Silver Particle Generator (SPG), a commercially available evaporation-condensation-based particle generator. The impact of the temperature on the particle size distributions generated is examined and the aerosol stability evaluated. Different salts are compared to evaluate their impact on the counting efficiency in CPCs. The SPG was able to generate aerosols efficiently while controlling particle sizes. The results showed that both operating temperature and particle composition had a significant impact on particle generation. Particle concentrations were observed to exceed 106 cm−3 at temperatures below 400 °C. The geometric mean diameter remained stable day-to-day, with less than 6% variation for two evaluated settings at 13 and 57 nm, respectively. The assessment of the counting efficiency for three different CPCs revealed that the salt composition has a significant impact on the 50% detection threshold diameter (d50) of a 23 nm CPC, which ranged from 8.5 to 32.7 nm. An evaluation of the counting efficiency of two 2.5 nm CPCs, based on butanol and water, showed a reduced influence of particle composition, particularly for the butanol-based model. Additionally, the water-based CPC showed an increased d50 diameter for the generated silver particles compared to the inorganic salts.
Source: Aerosol Science and Technology
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4409415556