The photoelectron spectra ofSiO2on silicon powder is measured with and without the addition of carbon black. Samples without carbon black show significant charging and peak deformation due to photoelectron emission. Samples containing carbon black show no evidence of charging. Furthermore, the contribution from carbon black can be subtracted from the overall signal in the valence band region to give valence band spectra of insulating powders. It is suggested that mixing carbon black with nonconducting powders may be an effective way to eliminate surface charging effects while at the same time providing a useful calibration standard. ©1997 American Institute of Physics.