Effect of ionic wind on the sample distribution in corona discharge ion mobility spectrometry

Ionic wind generated during corona discharge (CD) can significantly influence the airflow field within Ion Mobility Spectrometry (IMS), yet its impact is often overlooked. This study delves into the impact of ionic wind on sample distribution, emphasizing the need to balance reactant ion density and ionic wind intensity, which leads to sample dilution. To mitigate this issue, an axial injection mode employing a hollow needle was proposed, thereby improving the sensitivity and recovery performance of CD-IMS. As a result, the limit of detection of dimethyl methylphosphonate (DMMP) monomer is lowered from 15 ppbv to 5 ppbv. Furthermore, this technique was successfully applied to the detection of lithium battery electrolyte leaks, with carbonate concentrations as low as 10 mg/L or 1 nL being detected within 5 s. Such findings underscore the technique's applicability for swift and sensitive monitoring of battery safety.