Chemical and Biological Engineering ETDs

Publication Date

4-8-1970

Abstract

Wafers of well-characterized nickel oxide single crystal, with (110) faces, were etched in hydrochloric acid and reduced by hydrogen in a high vacuum system. Reduction took place at temperatures of 280-310°C and pressures of 1.0-1.3 torr. The reduced wafers were replicated by carbon film and the replicas were examined by an electron microscope.

A series of reduction patterns at various stages of surface change were obtained. After a period of incubation, hemispherical metallic nickel particles, about 400 A in diameter, appeared on the parent nickel oxide surface. The number of hemispheres increased but the size of the hemispheres did not change as reduction proceeded. The parent surface did not have any pits or hills around the hemispheres, but was flat. Surfaces of different Miller indices had different reactivities. Sintering phenomena occurred after full coverage of hemispheres on the parent surface.

Document Type

Dissertation

Language

English

Degree Name

Chemical Engineering

Level of Degree

Doctoral

Department Name

Chemical and Biological Engineering

First Committee Member (Chair)

George Heinz Quentin

Second Committee Member

Thomas Telisphore Castonguay

Third Committee Member

Kenneth Edward Cox

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