A new, compact Laser Ablation of Aerosol Particle Time-Of-Flight mass spectrometer (LAAP-TOF)

摘要

We present a compact bench top size single particle laser ablation aerosol mass spectrometer (LAAPTOF) measuring just 80 cm × 76 cm × 76 cm (w × d × h). The instrument features an aerodynamic particle lens inlet, a particle sizing region using two scattering lasers, a bipolar Time-Of-Flight mass spectrometer and an excimer laser for ablation/ionization of aerosol particles. The ablation laser operates at a wavelength of 193 nm with a power of up to 12 mJ /pulse (pulse duration ～10 ns). This wavelength allows for detection of pure NaCl and sulfate particles. The bipolar TOF analyzer simultaneously analyzes both ion polarities with a resolving power of M/ΔM ≥ 600 Th/Th FWHM for each polarity. Currently the instrument is able to analyze up to 100 particles/s.