Characterization and Applications of Combined Single Photon Ionization and Photoelectron Ionization Source

Abstract

The characters and applications of combined single photon ionization (spi) and photoelectron ionization (pei) source were introduced. the ion source can generate dominated molecular ions in spi mode and fragments ions same as standard el spectrum in pei mode. the switch time between the two modes was several microseconds. the limit of detection in spl mode was reduced by increasing the optical path in the ion source. achieved detection limits were 0. 05 ml/m(3) and 20 ml/m(3) for benzene in spi mode and so(2) in pei mode with accumulating time of 4 s respectively. products in the process for catalytic dehydrogenation of alkanes were monitored in spi mode. in addition, the samples of sf(6) were analyzed in pei mode with low energy electrons and the impurities were identified.