{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"80f80524e6b761eb195466f3b2bd5a21ba68794d2a4aaabda92ca7992cae0c72","created":"2026-10-03T07:17:58Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"70d3c88fcd5270ae0138fa1ca8da6b9153ed679f0a8fbd0c057d59149fae268e","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"identification","assisted_by":[],"external_id":"cm.contact-electrification.carrier-identity","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"When two insulators touch, charge moves between them, even though insulators have no free electrons. Experiments support electrons, ions such as hydroxide from adsorbed water, or torn-off bits of material, depending on the system.","posed_since":"","precise":"For polymer-polymer, polymer-oxide and identical-material contacts, with surface charge densities up to about $8\\,\\mathrm{statC}/\\mathrm{cm}^2$ (the air-breakdown limit), determine the fraction of transferred charge carried by electrons, ions ($\\mathrm{H}+$, $\\mathrm{OH}-$, other) and transferred material. Identification must be chemical or spectroscopic (x-ray photoelectron spectroscopy, mass spectrometry, isotope labeling) with a closed charge balance. An answer is a quantified carrier partition for a set of benchmark pairs.","problem_ref":null,"references":"","settled_by":"An experiment in which the transferred charge equals, within error, the chemically identified transferred species for each benchmark pair.","status_note":"","title":"Which species carry charge between contacting insulators","topic_ref":"6676ebb8ae9967cf0bd809e5691250afdfe45b670cf3dafe4fffa9bdff8cdab2"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"259f9967a8f1f8e13775135d434e80c884844ef9bcb06858d6fd043b3c928a24","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"6b0f3a0aef44b94ddd77876d97cf38938942593fea3579aec13f9f7e7b5bdcae","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"BgHHU7qcDgCxsPJXcARC6_gkQVg7OLDwwFt0xrOld__gfXLjuikA2eGAHR4DUfhHKIPW9sfTJCklqQTF46ShDA"},"schema":"pubphys.envelope/1"},"record_hash":"259f9967a8f1f8e13775135d434e80c884844ef9bcb06858d6fd043b3c928a24","leaf_index":918}