EELS of Lead (Pb)
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Table 2320a. Main edges of Pb used in EELS analysis. The listed energy windows are typically used for map and quantification.
Edge(s)
Edge onsets (eV)
Energy window (eV)
N6,7 ~138 145 - 240
M4,5 ~2500  
 
Table 2320b. Conditions commonly used to take energy filtered (EFTEM) images from Pb.
Edge(s)
Pre-edge (eV)
Post-edge(eV)
Slit width
Exposure time (s)
M4,5 2324 2534 100 40

The sandwich structure shown in Figure 2320a (a) is composed of three layers: SrTiO3, PbTiO3, and Pt. An amorphous Ti-rich interfacial layer as well as nanometer size precipitates was formed at PbTiO3/Pt interfaces. In the low-loss region in EELS from the different layers shown in Figure 2320a (b), the energy peaks labeled A–H for SrTiO3 and a–h for PbTiO3 are formed by interband transitions which are typical in bulk SrTiO3 and PbTiO3 [1]. The strong peaks H/h and H’/h’ arise from transitions of Ti 3p to higher energy levels such as Ti 3d, Ti 4s, forming Ti M2,3 edge. In the precipitates, the transitions h and h are reduced in intensity because these precipitates might be Ti-deficient. In Figure 2320a (c), the two core loss EELS profiles from SrTiO3 and PbTiO3 layers show clear splitting of the Ti-L2,3 edges, while for the interfacial layer the splitting at the Ti-L3 edge is much less and the splitting at the Ti-L2 edge disappears. The splitting of Ti-L2,3 edges reflects the hybridization and ligand field strength of Ti–O atomic interaction so that the reduction of splitting in the interfacial layer reflects the weaker Ti–O bonding force. Due to the similar hybridization of O 2p states with Ti 3d in the conduction band, the energy region from 530 eV to 536 eV is split into two subbands t2g (marked peak 1) and eg (marked peak 2). Figure 2320a (d) shows the EEL spectra of Pb- and Pt-M4,5 edges.

SrTiO3, PbTiO3, and Pt

Figure 2320a. (a) TEM image of sandwich structure ( SrTiO3, PbTiO3, and Pt), and (b) low-loss region in EELS, (c) Ti-L2,3 and O-K edges, and (d) Pb- and Pt-M4,5 edges from the different layers. The black arrows in (d) denote the positions of Pt-M4,5 edges. Adapted from [2]

Figure 2320b shows an EEL spectrum taken from a lead zirconate titanate (Pb(Zr0.3Ti0.7)O3, PZT) thin film.

EEL spectrum taken from a lead zirconate titanate (Pb(Zr0.3Ti0.7)O3, PZT) thin film

Figure 2320b. EEL spectrum taken from a lead zirconate titanate (Pb(Zr0.3Ti0.7)O3, PZT) thin film. [3]

 

 

 

 

 

 

 

 

[1] K. V. Benthem, C. Elsasser, and R. H. French, J. Appl. Phys. 90, 6156 (2001).
[2] L. F. Fu, S. J. Welz, and N. D. Browning, M. Kurasawa, and P. C. McIntyre, Z-contrast and electron energy loss spectroscopy study of passive layer formation at ferroelectric PbTiO3/Pt interfaces, Applied Physics Letters, 87, 262904 (2005).
[3] Harkins, P. and MacKenzie, M. and Craven, A.J. and McComb, D.W. (2008) Quantitative electron energy-loss spectroscopy (EELS) analyses of lead zirconate titanate. Micron, 39 (6). pp. 709-716.

 
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