Spatially resolved density measurements of singlet delta oxygen in a non-equilibrium atmospheric pressure plasma jet by molecular beam mass spectrometry
Jingkai Jiang, Yolanda Aranda Gonzalvo, Peter Bruggeman
Abstract
Abstract Singlet delta oxygen (O 2 ( a 1 Δ g )), the first electronically excited state of O 2 , plays an important role in many applications. We report the first measurements of absolute densities of O 2 ( a 1 Δ g ) in an atmospheric pressure plasma jet (APPJ) by molecular beam mass spectrometry (MBMS). The ability to measure axial and radial profiles of O 2 ( a 1 Δ g ) impinging on a substrate in the effluent of the APPJ is a key advantage of the MBMS diagnostic method over previously reported optical methods. The measured large O 2 ( a 1 Δ g ) densities in the APPJ effluent, up to one order of magnitude higher than the O density, underline the potential importance of O 2 ( a 1 Δ g ) in many applications using APPJs.