Design of ion migration spectrum system based on four vacuum ultraviolet lamps

An ion migration spectrometry (IMS) system for the separation and detection of trace molecules was developed using four vacuum ultraviolet lamps as ionization sources. The IMS system of the four vacuum UV lamp has a larger ionization region, and the number of gas molecules captured by it is more and the number of ions generated is more under the same gas concentration, and the use of PCB splice method to build an ion migration tube, the electrode spacing can reach 2 mm, the smaller the spacing, the more uniform the internal electric field, thereby reducing the ion diffusion phenomenon. Both methods improve the sensitivity of ion migration spectra and reduce the minimum detection limit. The sensitivity of IMS system was analyzed experimentally by using a mixture of isobutene gas and pure air. The experimental results showed that the four-vacuum ultraviolet lamp system could detect isobutene gas with a concentration below 0.3 ppm, providing a reliable solution for trace molecular detection.