title: Effect that the relative abundance of copper oxide and zinc oxide corrosion has on the visualization of fingerprints formed from fingerprint sweat corrosion of brass.
abstract: From an examination of the fingerprint sweat corrosion of 40 different individuals on α phase brass, we show that an increase in visualization can be achieved by applying a negative potential to the brass followed by the introduction of a conducting powder. Previously, this technique has been demonstrated only for a positive applied potential and a corrosion product that was dominated by p-type copper (I) oxide. X-ray photoelectron and Auger electron spectroscopic analyses of the surface of the corroded brass show that an increase in visualization with a negative applied potential corresponds with an increase in the concentration of n-type zinc oxide relative to p-type copper (I) oxide with the Cu:Zn ratio <0.8:1. Work function conditions for the formation of an n-type zinc oxide/brass rectifying Schottky barrier are fulfilled.
authors.affiliation: Scientific Support Department, Northamptonshire Police, Wootton Hall, Northampton NN4 0JQ, UK. john.bond@northants.police.uk
authors.forename: John W
authors.initials: JW
authors.lastname: Bond
mesh_terms: D003300:Copper / Q000737:chemistry*; D003343:Corrosion; D003878:Dermatoglyphics; D006801:Humans; D011208:Powders; D013057:Spectrum Analysis / Q000379:methods; D013542:Sweat; D014131:Trace Elements / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*; D015034:Zinc Oxide / Q000737:chemistry
chemical_list: D011208:Powders; D014131:Trace Elements; C048399:brass; D003300:Copper; D015032:Zinc; D015034:Zinc Oxide; C030973:cupric oxide