{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"65e46a2fd412c1182a36a869ce6e6e44b95e0a9316976a19b6dc707fd9733fdd","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["259f9967a8f1f8e13775135d434e80c884844ef9bcb06858d6fd043b3c928a24","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"f6b3698b065e116a17be7e9f2f59cf916b8ecfa4a81b3f1ac77af4b1c13f6a07","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":"2","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":"259f9967a8f1f8e13775135d434e80c884844ef9bcb06858d6fd043b3c928a24","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":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"4e05700c011000ddfd80f238efd57a503cf43f095653ec94c2a9987f41b8eb6f","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"5c5f015662ef88026c92fad96d2b95abd79feddd15b4d89ae6d3abda78f831b7","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"zvcz9kPHGfqE1gTcCP8r4rHBmXQKY1SHaqIpE_GO5ZsoDeSYEigCA2xMLsLXnoOZN2Q-PidDcYUIp4XGu3a0BQ"},"schema":"pubphys.envelope/1"},"record_hash":"4e05700c011000ddfd80f238efd57a503cf43f095653ec94c2a9987f41b8eb6f","leaf_index":2706}