Development of a high-efficiency high-resolution particle-induced x-ray emission system for chemical state analysis of environmental samples

Rev Sci Instrum. 2007 Jul;78(7):073105. doi: 10.1063/1.2756623.

Abstract

We have developed a high-efficiency high-resolution particle-induced x-ray emission (PIXE) system employing a von Hamos-type crystal spectrometer for a chemical state identification of trace elements in environmental samples. The energy resolution of the system was determined to be about 0.05% through the observation of Si Kalpha(1,2) x rays (1.74 keV) from elemental silicon. The throughput efficiency of the system was also evaluated quasitheoretically to be 1.6x10(-7) counts/incident proton for Si Kalpha(1,2) emission. To demonstrate a chemical state analysis using the high-resolution PIXE system, Si Kalpha(1,2) and Kbeta x-ray spectra for SiC, Si(3)N(4), and SiO(2) were measured and compared. The observed chemical shifts of the Si Kalpha(1,2) peaks for SiC, Si(3)N(4), and SiO(2) relative to elemental silicon were 0.20, 0.40, and 0.55 eV, respectively. The tendency of these shifts were well explained by the effective charges of the silicon atoms calculated by a molecular orbital method.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Environmental Monitoring / instrumentation*
  • Environmental Monitoring / methods
  • Equipment Design
  • Equipment Failure Analysis
  • Microchemistry / instrumentation*
  • Microchemistry / methods
  • Particle Size
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Specimen Handling / instrumentation*
  • Specimen Handling / methods
  • Spectrometry, X-Ray Emission / instrumentation*
  • Spectrometry, X-Ray Emission / methods