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The application of liquid metals such as gallium, tin and lithium as plasma-facing materials is a potential means to resolve the technical issues associated with power exhausting and particle handing in magnetic fusion devices. GaInSn alloy with melting point of 10.5°C, is employed as a modeling material to explore the plasma-driven permeation (PDP) method to study the hydrogen isotopes (hydrogen and deuterium) transport parameters in a liquid metal. Static liquid GaInSn membranes sitting on a mesh sheet are exposed to hydrogen/deuterium plasmas in the linear plasma device VEHICLE-1 with the temperature range of 280–496°C. Hydrogen/deuterium diffusivity are obtained by fitting the time evolutions of permeation fluxes. The dynamic hydrogen/deuterium retention in the liquid GaInSn are found to be low (∼1015D/cm3), which are consistent with the thermal desorption spectroscopy (TDS) measurement following plasma exposure. The hydrogen and deuterium transport parameters are found to be close to each other. Keywords: Liquid metal, Plasma-driven permeation, Diffusivity, Recombination coefficient, Retention

Steady state hydrogen, deuterium and helium plasma interactions with a liquid metal: Ga67In20.5Sn12.5 at termperatures between room temperature and ∼250°C have been investigated with JxB-forced convection, using a laboratory-scale facility: VEHICLE-1. Noticeably reduced recycling has been observed for all these gases, when JxB-forced convection is applied, under respevtive plasma bombardment. Preliminary fluid dynamics modeling has been done to interpret experimental observations. For hydrogenic species, a trend has been found, indicating temperature-dependent retention saturation levels. With thermal desorption spectrometry, the amount of deuterium retention after saturation at ∼250°C has been evaluated to be of the order of 1014D/cm3 whereas the retention of inert gases is found to be undetectable.