Abstract: A display device and a method for making and operating the display device are described. The display device comprises a base plate containing at least one emitter, a display screen, and a spacer located between the base plate and display screen, where the spacer has a high concentration of an emitter-cleaning material. The spacer may comprise a xerogel or aerogel material and the emitter-cleaning material may comprise hydrogen. The spacer and a method for making the spacer and using the spacer to clean an emitter are also described. The spacer material cleans the emitter by absorbing gases during fabrication of the display device and desorbing emitter-cleaning gases during operation of the display device. By keeping the emitter clean, the spacer retains the work function of the emitter at a low level, thereby prolonging the usefulness of the display device.