The spectral response, brightness, and outgassing characteristics of new, low-voltage phosphors for application in field emission flat panel displays, are presented. The tested phosphor materials include combustion synthesized powders and thin films prepared by rf diode or magnetron sputtering, laser ablation, and molecular beam epitaxy. These cathodoluminescent materials are tested with e-beam excitation at currents up to 50 mu A within the 200-2000 V (e.g., "low-voltage") and 3-8 kV (e.g., "medium-voltage") ranges. The spectral coordinates are compared to commercial low-voltage phosphors. Phosphor outgassing, as a function of time, is measured with a residual gas analyzer at fixed 50 mu A beam current in the low-voltage range. We find that levels of outgassing stabilize to low values after the first few hours of excitation. The desorption rates measured for powder phosphor layers with different thicknesses are compared to desorption from thin films.