X-ray photoelectron microscopic imaging of the chemical bonding state of Si in a rock sample

H. Seyama 1 *, D. Wang 2, M. Soma 3

1National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan

2Ulvac-Phi Inc., 370 Enzo, Chigasaki, Kanagawa 253-0084, Japan

3University of Shizuoka, 52-1 Yada, Shizuoka, Shizuoka 422-8526, Japan

email: H. Seyama (seyamah@nies.go.jp)

*Correspondence to H. Seyama, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.

Keywords

XPS • imaging • microscopy • rock • silicate mineral

Abstract

A microscopic surface analytical technique is desirable for detailed studies of environmental and geochemical surface processes because most of the relevant solid components from natural sources are heterogeneous and have intricate microstructures. Recent advances in XPS instrumentation have allowed chemical mapping of surfaces. This paper demonstrates the imaging of the chemical bonding state of Si in a rock sample (granodiorite) by X-ray photoelectron microscopy. An Si 2p photoelectron image of the granodiorite was acquired from the boundary between the quartz and biotite phases, and the image was deconvoluted into quartz and biotite components on the basis of the difference (chemical shift) between the Si 2p binding energies of the two minerals. The two phases were clearly distinguishable in the chemical-bonding-state images for Si. Copyright © 2004 John Wiley & Sons, Ltd.