Generation of hard X-ray radiation using the triboelectric effect by peeling adhesive tape

• X-ray production by adhesive tape depends on the polar part of the surface energies.
• X-ray generation is suppressed if the adhesion force crosses a maximum.
• A maximum photon count rate of approx. 500 counts per second was observed.
• X-ray output of metal–polymer contacts depends on the work function of the metal.
• This may be used to determine the highest occupied surface state of the polymer.

The triboelectric effect describes electrical charging when bringing different materials into contact. We report on the generation of hard X-ray radiation by peeling various adhesive tapes under medium vacuum conditions. Beside vacuum housing and pumps as instrumentation only an electric motor, two rolls and a metal foil as target material are necessary. The spectral distribution of generated X-rays was analyzed using an energy-dispersive detector. Depending on peeling speed, pressure and choice of material combination, electrons with energies sufficient to excite emission in the hard X-ray region are produced. The results are discussed in terms of triboelectric separation of charge carriers.