002 a a nd 0 t 100 101 003 ooe 105 005

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: of the pure T iS to expand linearly with increasing values of x = 2 w ere found 0 to x 5 0 . 1 5 , s upporting the interpretation by S choltz e t. al. (31) and Gerards e t . al. ( 65) t hat the silver atoms behave like a dilute gas which initially uniformly populate the Van der Waals gaps in the host T iS 2 c rystal. The lattice parameters w ere plotted as a function of silver mole fraction in Fig. 14a and P i g . 1 4 b . T he lattice parameters of the samples where 0.15 < x < 0 .3-0 w ere identified from the position of the diffraction lines to be pure stage 2 s amples. Silver mole fractions in the range 0 .3 < x < 0 . 5 w ere predominantly stage 2 w ith small amounts of stage 1 present. Figures 14a and 1 4 b r epresent a graphical summary of the X-ray diffraction results of the Group A s amples (quenched from 8 00 C). P ure P age -28a- F igure 14a H exagonal lattice parameter a ( A ) versus silver mole fraction x for the group A s amples. t+ dilute S tage 2 F igure 1 4b Hexagonal lattice parameter c ( A ) v ersus silver mole fraction x for the group A s amples. 0 5 .8 I{ I -f dilute + I Stage 2 Page - 2 9 - s ilver diffraction lines were present for all samples w i t h x> 0.5 m eaning that t he h igh c oncentration samples ( x > 0 . 5 w ere not completely i n t e r c a l a t e d , and that crystalline silver was present in addition to Ag T i S x 2' T h e samples with x > 0 . 5 w ere eliminated from all future work o n the basis of the X-ray d a t a . lines for Ag There was no evidence of pure silver diffraction 0.5 T i S 2 i n contrast with results obtained by S choltz e t . a l . ( 4 5 ) who reported t hat t he maximum mole fraction of silver that could be intercalated electrochemically or thermally was x 0.42. T h e group A samples (cooled from 8 0 0 C ) a gree w i t h the results obtained by Scholz e t . a l . (63) and Gerards e t . al. (65) only for values of 0 < x < 0 . 2 5 . T h e higher silver concentration samples ( x > 0 . 2 5 ) p repared for this work at 8 0 0 C a re predominantly stage 2 i n contrast with the predominantly stage 1 s tructures reported b...
View Full Document

This note was uploaded on 10/08/2009 for the course CME MAT E 630 taught by Professor Dr. during the Fall '09 term at University of Alberta.

Ask a homework question - tutors are online