TY - JOUR
T1 - Phase transformation and chemical decomposition of nanocrystalline SnO2 under heavy ion irradiation
AU - Cusick, Alex B.
AU - Lang, Maik
AU - Zhang, Fuxiang
AU - Zhang, Jiaming
AU - Kluth, Patrick
AU - Trautmann, Christina
AU - Ewing, Rodney C.
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/9/15
Y1 - 2017/9/15
N2 - A crystalline-to-crystalline phase transformation, including chemical decomposition, has been observed in SnO2 nanopowder irradiated by 2.2 GeV 197Au ions. X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM) were used to characterize the transformation from tetragonal SnO2 (P42/mnm) to tetragonal SnO (P4/nmm), with trace quantities of β-Sn (I41/amd). At a fluence of approximately 2.0 × 1012 ions/cm2, diffraction maxima corresponding to SnO became clearly evident and increased in intensity as fluence increased. The proportion of SnO, as determined by Rietveld refinement of XRD data, reached 23.1 ± 0.8% at the maximum fluence investigated of 2.4 × 1013 ions/cm2. Raman spectra show high photoluminescence (PL) intensity before and during initial SnO formation, indicating the importance of oxygen vacancies in the transformation process. Small-angle X-ray scattering (SAXS) analysis provided evidence of ion tracks, but no tracks were observed using high-resolution TEM (HRTEM). The transformation likely occurs through a multiple-impact mechanism, based on the accumulation of O vacancies, defect ordering, and partially localized Sn reduction.
AB - A crystalline-to-crystalline phase transformation, including chemical decomposition, has been observed in SnO2 nanopowder irradiated by 2.2 GeV 197Au ions. X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM) were used to characterize the transformation from tetragonal SnO2 (P42/mnm) to tetragonal SnO (P4/nmm), with trace quantities of β-Sn (I41/amd). At a fluence of approximately 2.0 × 1012 ions/cm2, diffraction maxima corresponding to SnO became clearly evident and increased in intensity as fluence increased. The proportion of SnO, as determined by Rietveld refinement of XRD data, reached 23.1 ± 0.8% at the maximum fluence investigated of 2.4 × 1013 ions/cm2. Raman spectra show high photoluminescence (PL) intensity before and during initial SnO formation, indicating the importance of oxygen vacancies in the transformation process. Small-angle X-ray scattering (SAXS) analysis provided evidence of ion tracks, but no tracks were observed using high-resolution TEM (HRTEM). The transformation likely occurs through a multiple-impact mechanism, based on the accumulation of O vacancies, defect ordering, and partially localized Sn reduction.
KW - Decomposition
KW - Irradiation
KW - Nanocrystalline
KW - Phase transformation
KW - Reduction
KW - Swift heavy ions
KW - Tin oxide
UR - http://www.scopus.com/inward/record.url?scp=85019715755&partnerID=8YFLogxK
U2 - 10.1016/j.nimb.2017.05.037
DO - 10.1016/j.nimb.2017.05.037
M3 - Article
SN - 0168-583X
VL - 407
SP - 10
EP - 19
JO - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
JF - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
ER -