The absence of redox reactions for palladium(II) and copper(II) on electrostatically charged Teflon: Relevance to the concept of "cryptoelectrons"

Rub-a-dub-dub: The hypothesis of contact electrification through the transfer of cryptoelectrons was tested by scrutinizing the evidence for the reduction of Pd²⁺ and Cu²⁺ by static charges on rubbed Teflon. X-ray photoelectron spectroscopy studies indicated that neither of these ions is reduced (see picture; black: Pd²⁺ adsorbed, red: Pd ⁰ adsorbed and then reduced by formadehyde, green: mixture of Pd ²⁺ and Pd⁰ arising from partial reduction after 2 h under the XPS probe) by the static charge. The presented alternative interpretation challenges the role of cryptoelectrons.