Редколлегия Физикохимия Поверхности и Защита Материалов - Heterophase Metalframe0Oxide Structures Formed in a Range of Low-Temperature Activation of Iron. 1.

Heterophase MetalOxide Structures Formed in a Range of Low-Temperature Activation of Iron. 1. 3D-Video-Microprobing Reflectometry

Institute of Physical Chemistry, Russian Academy of Sciences, Leninskii pr. 31, Moscow, 119991 Russia

E-mail: Этот e-mail защищен от спам-ботов. Для его просмотра в вашем браузере должна быть включена поддержка Java-script

Abstract — Investigation of the morphology and composition of a nonuniform layer formed on the iron surface upon an hour of oxidation at an oxygen pressure of 0.001 to 10 mmHg and a temperature of 300 frame1

is carried out. Computer digital optical images of a small probed surface site upon digital processing enable us to introduce and estimate parameters of the morphological heterogeneity of the surface thermo-oxide layer, which affect its functional characteristics. By the data of morphological investigations (3D probe), the oxide layer has a heterogeneous multilayer structure and consists of a magnetite phase layer adjacent to the metal and an external hematite microcrystalline layer. At an increase in the oxygen pressure from 0.1 to 10 mmHg,

-Fe₂O₃ plates grow on the magnetite surface and gradually cover the whole surface forming a closely packed structure. In this case, the external oxide layer is composed of thin hematite microplates separated with clearly seen nano-size intergranular domains characterized by a high superficial micro-order and nano-heterogeneity in the oxide depth, which may explain pronounced functional, semiconducting, catalytic, and sensor properties, as well as the heightened reactivity of iron and its alloy oxidized in the range of a low-temperature activation.