Bond John W
Northamptonshire Police, Force HQ, Wootton Hall, Northampton NN4 OJQ, UK.
J Forensic Sci. 2011 Sep;56(5):1277-82. doi: 10.1111/j.1556-4029.2011.01808.x. Epub 2011 May 19.
Corrosive electrochemical processes of brass, including those resulting from fingerprint sweat, continue to be studied because of the widespread industrial use of brass. Here, we examine how increased temperature affects the relative abundance of fingerprint sweat corrosion products and the rectifying Schottky barrier formed between p-type copper (I) oxide corrosion and brass. X-ray photoelectron spectroscopy confirms increasing dezincification with increasing temperature. This leads to n-type zinc oxide replacing copper (I) oxide as the dominant corrosion product, which then forms a rectifying Schottky barrier with the brass, instead of copper oxide, when the temperature reaches c. 600°C. Using X-ray diffraction, resulting diodes show polycrystalline oxides embedded in amorphous oxidation products that have a lower relative abundance than the diode forming oxide. Conventional current/voltage (I/V) characteristics of these diodes show good rectifying qualities. At temperatures between c. 100 and c. 600°C, when neither oxide dominates, the semiconductor/brass contact displays an absence of rectification.
由于黄铜在工业上的广泛应用，其腐蚀电化学过程，包括由指纹汗液导致的腐蚀过程，仍在持续研究中。在此，我们研究了温度升高如何影响指纹汗液腐蚀产物的相对丰度，以及在p型氧化亚铜腐蚀产物与黄铜之间形成的整流肖特基势垒。X射线光电子能谱证实，脱锌现象随温度升高而增加。这导致n型氧化锌取代氧化亚铜成为主要腐蚀产物，当温度达到约600°C时，n型氧化锌与黄铜形成整流肖特基势垒，而非氧化铜。通过X射线衍射分析发现，所得二极管中的多晶氧化物嵌入非晶态氧化产物中，这些非晶态氧化产物的相对丰度低于形成二极管的氧化物。这些二极管的传统电流/电压（I/V）特性显示出良好的整流性能。在约100至约600°C的温度范围内，当两种氧化物都不占主导时，半导体/黄铜接触界面不存在整流现象。
