A triboelectric x-ray source

A source of x-rays capable of exciting the characteristic emission lines of Mo and Ag is demonstrated. The device, which requires no external high voltage supply, uses the triboelectric effect to produce a charge imbalance when silicone and a metal-loaded epoxy are made to repeatedly contact each other in vacuum. This provides a source of 40 keV electrons which generate bremsstrahlung and characteristic x-rays at a rate of $>105$ per contact cycle. By increasing the repetition rate of the contact cycle the viability of a device that emits $108x-ray$ photons per second is suggested, making triboelectricity an inexpensive source of x-rays. The form factors and simplicity of such devices open up interesting possibilities for x-ray imaging.