Chemical Activity of Fresh Aluminum Surfaces Formed by Scratching in High Vacuum

Abstract

Chemical activity of fresh aluminum surfaces were investigated by a newly developed method. Pressure decrease owing to chemisorption of organic compounds were monitored by a quadrupole mass spectrometer. The adsorption activity of organic compounds increased as in an order of ethers<alcohols<carbonyl compounds. Benzene and 1-hexene which have ic-electrons exhibited no chemical activity to fresh aluminum surfaces. Hydrogen evolution due to decomposition of chemisorbed molecules was observed during scratching. The desorption rate increased linearly with adsorption rate excepted for water. A large amount of hydrogen was produced from adsorbed water molecules during scratching. Reactivity of ROR' type compounds on fresh aluminum surface was ranked as follows: ethers<alcohols<water.