Highly sensitive detection of sulfur hexafluoride based on PEI-FAIMS

SF<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</inf> (sulfur hexafluoride) is widely and extensively used in electrical systems, and its leakage can significantly reduce the insulation performance of equipment. This paper combines the photoelectric effect ion source with high-field asymmetric waveform ion mobility spectrometry (FAIMS) to achieve high-sensitivity detection of SF<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</inf>. The study investigates the influence of operating current and repelling voltage on ionization efficiency, and determines the detection limit of SF<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</inf>. Experimental results indicate that increasing the operating current enhances the UV-LED light flux, thereby improving the ionization efficiency of the photoelectric effect ion source. Applying an appropriate negative voltage to the electron emitter significantly increases ionization efficiency, with the optimal repelling voltage for SF<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</inf> determined to be -2 V. There is good linearity between SF<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</inf> concentration and response signal, and the detection limit is 0.019 ppm.