NASA Selects Tethers Unlimited’s HYDROS-C for Flight in Early 2019
NASA has selected TUI's HYDROS-C thruster for demonstration on the first Pathfinder Technology Demonstration (PTD) CubeSat mission, planned for launch in early 2019.
The HYDROS-C propulsion unit is tiny—just 1U in size. NASA also has a nice video up showing PTD-1 in action.
I can’t find specific launch details yet, but the best I can find is that its launch is part of the ELaNa program.